title: make <package> implies new Extracting
body: <p>I created a Buidroot package with the both following files : </p>
  
  <p>.mk </p>
  
  <pre><code>AVM_VERSION = $(BR2_PACKAGE_AVM_TARGET)-V00.00.01
  AVM_SITE_METHOD = git
  AVM_SITE = ssh://git@myownserver.com/App/AVM.git
  
  AVM_INSTALL_TARGET = YES
  
  define AVM_BUILD_CMDS   
      $(TARGET_CC) $(TARGET_CFLAGS) -o $(@D)/AVM $(@D)/avm.c    
  endef
  
  define AVM_INSTALL_STAGING_CMDS 
      $(MAKE) DESTDIR=$(STAGING_DIR) -C $(@D) install
  endef
  
  define AVM_INSTALL_TARGET_CMDS
      $(INSTALL) -D -m 0755 $(@D)/AVM $(TARGET_DIR)/usr/bin/avm
  endef
  
  $(eval $(generic-package))
  </code></pre>
  
  <p>Config.in</p>
  
  <pre><code>config BR2_PACKAGE_AVM
      bool "AVM"
      help
        Application for embedded platform.
  
  config BR2_PACKAGE_AVM_TARGET
      string "AVM package target"
      depends on BR2_PACKAGE_AVM
      help
          Define board
  </code></pre>
  
  <p>I succedded in compiling the package by using the above .mk file. However, because I wanted to modify the source code into output/build I note the following behavior (After removing only .stamp_built) : </p>
  
  <pre><code>$ make AVM
  &gt;&gt;&gt; AVM v00.00.01 Extracting
  ...
  &gt;&gt;&gt; AVM v00.00.01 Patching
  &gt;&gt;&gt; AVM v00.00.01 Configuring
  &gt;&gt;&gt; AVM v00.00.01 Building
  ...
  </code></pre>
  
  <p>I obtain a new Extracting, Patching, Configuring, Building even if no .stamp removed...</p>
  
  <p>What's wrong ?  </p>
  
  <p>EDIT : </p>
  
  <p>The problem seems to come from the AVM_VERSION definition. When I exchange <code>$(BR2_PACKAGE_AVM_TARGET)</code> by its value I am getting <code>make: Nothing to do for « AVM ».</code></p>
  
  <p>This variable, named $(BR2_PACKAGE_AVM_TARGET), has been defined into the defconfig file associated to the board as <code>BR2_PACKAGE_AVM_TARGET="AVM2.3"</code></p>