Fix incorrect PROC/ENDP match

The conversion script was incorrectly matching
CONFIG_POSTPROC[_VISUALIZER] and generating an
incorrect vpx_config.asm

Match both PROC and ENDP on word boundaries

Change-Id: Ic2788c3b522d4ee0afc5223b72e1b09fb52645be

build/make/ads2gas_apple.pl

diff --git a/build/make/ads2gas_apple.pl b/build/make/ads2gas_apple.pl
index 78f4a97..a9740a8 100755
--- a/build/make/ads2gas_apple.pl
+++ b/build/make/ads2gas_apple.pl
@@ -157,8 +157,8 @@
     s/\sPRESERVE8/@ PRESERVE8/g;
 
     # Strip PROC and ENDPROC
-    s/PROC/@/g;
-    s/ENDP/@/g;
+    s/\bPROC\b/@/g;
+    s/\bENDP\b/@/g;
 
     # EQU directive
     s/(.*)EQU(.*)/.set $1, $2/;