BaseTools: Remove Makefile/MakefileName fields

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3653

The Makefile and MakefilName fields are never set/used. Remove them.
To check this, the following commands can be used:
- grep -rIn "\.Makefile"
- grep -rIn "\.MakefileName"

Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
Reviewed-by: Chris Jones <christopher.jones@arm.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>
Reviewed-by: Bob Feng <bob.c.feng@intel.com>

BaseTools/Source/Python/build/build.py

@@ -2186,8 +2186,6 @@ class Build():
             Pa.CreateLibModuelDirs()
             # Fetch the MakeFileName.
             self.MakeFileName = Pa.MakeFileName
-            if not self.MakeFileName:
-                self.MakeFileName = Pa.MakeFile
 
             Pa.DataPipe.DataContainer = {"LibraryBuildDirectoryList":Pa.LibraryBuildDirectoryList}
             Pa.DataPipe.DataContainer = {"ModuleBuildDirectoryList":Pa.ModuleBuildDirectoryList}