ENH: Support inplace clip (#15388)
 - [V] closes #15388
 - [V] tests added / passed
 - [V] passes ``git diff upstream/master --name-only -- '*.py' | flake8 --diff``
 - [x] whatsnew entry

note this doesn't offer any perf benefit (actually doing this is a bit tricky), but ok. # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=h1) Report
> :exclamation: No coverage uploaded for pull request base (`master@044feb5`). [Click here to learn what that means](https://docs.codecov.io/docs/error-reference#section-missing-base-commit).
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/16462/graphs/tree.svg?height=150&src=pr&token=eZ4WkYLtcO&width=650)](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=tree)

```diff
@@            Coverage Diff            @@
##             master   #16462   +/-   ##
=========================================
  Coverage          ?   90.42%           
=========================================
  Files             ?      161           
  Lines             ?    51036           
  Branches          ?        0           
=========================================
  Hits              ?    46151           
  Misses            ?     4885           
  Partials          ?        0
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.26% <100%> (?)` | |
| #single | `40.16% <19.04%> (?)` | |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/generic.py](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZ2VuZXJpYy5weQ==) | `92.16% <100%> (ø)` | |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=continue).
> **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta)
> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=footer). Last update [044feb5...2e7f8c1](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=h1) Report
> Merging [#16462](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/d7962c50df5edcee19d6fce80a030eef9a3c7ae4?src=pr&el=desc) will **increase** coverage by `0.02%`.
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/16462/graphs/tree.svg?width=650&height=150&src=pr&token=eZ4WkYLtcO)](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #16462      +/-   ##
==========================================
+ Coverage   90.39%   90.42%   +0.02%     
==========================================
  Files         161      161              
  Lines       51036    51045       +9     
==========================================
+ Hits        46136    46159      +23     
+ Misses       4900     4886      -14
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.26% <100%> (+0.02%)` | :arrow_up: |
| #single | `40.16% <19.04%> (-0.01%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/generic.py](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZ2VuZXJpYy5weQ==) | `92.16% <100%> (+0.03%)` | :arrow_up: |
| [pandas/util/testing.py](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=tree#diff-cGFuZGFzL3V0aWwvdGVzdGluZy5weQ==) | `80.79% <0%> (+0.19%)` | :arrow_up: |
| [pandas/plotting/\_converter.py](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=tree#diff-cGFuZGFzL3Bsb3R0aW5nL19jb252ZXJ0ZXIucHk=) | `65.05% <0%> (+1.81%)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=continue).
> **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta)
> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=footer). Last update [d7962c5...62ee43b](https://codecov.io/gh/pandas-dev/pandas/pull/16462?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 @jreback, thanks. I fixed all of the comments and pushed to my branch. thanks!