BaseTools: Remove unused logic for EDKI

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=1350
Remove EDK module type support from BaseTools python code.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Jaben Carsey <jaben.carsey@intel.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

BaseTools/Source/Python/Common/GlobalData.py

@@ -13,13 +13,7 @@
 import re
 
 gIsWindows = None
-
-gEdkCompatibilityPkg = "EdkCompatibilityPkg"
 gWorkspace = "."
-gEdkSource = "EdkCompatibilityPkg"
-gEfiSource = "."
-gEcpSource = "EdkCompatibilityPkg"
-
 gOptions = None
 gCaseInsensitive = False
 gAllFiles = None