BaseTools: silence parentheses-equality warning

Some code generated by antlr causes clang to emit warning
warning: equality comparison with extraneous parentheses
  [-Wparentheses-equality]
The warning is suppressed specifically for clang without affecting other
compilers.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Zenith432 <zenith432@users.sourceforge.net>
Reviewed-by: Liming Gao <liming.gao@intel.com>
(cherry picked from commit 4e97974c1e)

BaseTools/Source/C/VfrCompile/Pccts/antlr/antlr.c

@@ -41,6 +41,7 @@ ANTLR_INFO
 #pragma warn -aus  /* unused assignment of 'xxx' */
 #endif
 
+#pragma clang diagnostic ignored "-Wparentheses-equality"
 
 #ifdef __USE_PROTOS
 static void chkToken(char *, char *, char *, int);

BaseTools/Source/C/VfrCompile/Pccts/antlr/antlr.g

@@ -53,6 +53,7 @@
 #pragma warn -aus  /* unused assignment of 'xxx' */
 #endif
 
+#pragma clang diagnostic ignored "-Wparentheses-equality"
 
 #ifdef __USE_PROTOS
 static void chkToken(char *, char *, char *, int);