1. Replace PeCoffLoader library by PeCoff lib for PeiCore, DxeIpl and DxeMain.

2. Add three PeCoff library instances for NT32 PeImage load.
3. Update PeCoffGetEntryPointLib to support TeImage.


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@3965 6f19259b-4bc3-4df7-8a09-765794883524

MdePkg/Include/Library/PeCoffLib.h

@@ -202,5 +202,22 @@ PeCoffLoaderRelocateImageForRuntime (
   )
 ;
 
+/**
+  Unloads a loaded PE/COFF image from memory and releases its taken resource.
+   
+  For NT32 emulator, the PE/COFF image loaded by system needs to release.
+  For real platform, the PE/COFF image loaded by Core doesn't needs to be unloaded, 
+  this function can simply return RETURN_SUCCESS.
 
+  @param  ImageContext              Pointer to the image context structure that describes the PE/COFF
+                                    image to be unloaded.
+
+  @retval RETURN_SUCCESS            The PE/COFF image was unloaded successfully.
+**/
+RETURN_STATUS
+EFIAPI
+PeCoffLoaderUnloadImage (
+  IN PE_COFF_LOADER_IMAGE_CONTEXT  *ImageContext
+  )
+;
 #endif