### Description

Using the `src` parameter when joining a multicast feed results in `Feature Not Supported` error. I'm running the latest revision of GPAC on Rocky 8. Without the filtering GPAC receives traffic from 2 sources which isn't working either. When using TSDuck I'm able to join the source specific multicast using
```
tsp -I ip --ssm 10.1.2.3@239.1.2.3:1234
```
Using GPAC I'm trying the following:
```
gpac -i udp://239.1.2.3:port=1234:src=10.1.2.3
```
It results in `Failed to load filter for "udp://239.1.2.3:port=1234:src=10.1.2.3": Feature Not Supported` however.
Source filtering for UDP multicast not working
This is a GitHub Issue
repo:gpac
owner:gpac
Title : Source filtering for UDP multicast not working
Issue date:

--- start body ---
### Description

Using the `src` parameter when joining a multicast feed results in `Feature Not Supported` error. I'm running the latest revision of GPAC on Rocky 8. Without the filtering GPAC receives traffic from 2 sources which isn't working either. When using TSDuck I'm able to join the source specific multicast using
```
tsp -I ip --ssm 10.1.2.3@239.1.2.3:1234
```
Using GPAC I'm trying the following:
```
gpac -i udp://239.1.2.3:port=1234:src=10.1.2.3
```
It results in `Failed to load filter for "udp://239.1.2.3:port=1234:src=10.1.2.3": Feature Not Supported` however.
--- end body ---
