Compiler: Improve the reported line number accuracy on warning 203/4 (symbol never used).

Imported from Pawn 3.1.3541+.
https://code.google.com/p/pawnscript/source/detail?r=25

plugins/ns/nscommands.sma

@@ -14,7 +14,7 @@
 #include <amxmodx>
 #include <amxmisc>
 
-#pragma tabsize 0
+#pragma tabsize 4
 
 new g_TeamOneAck[12];
 new g_TeamTwoAck[12];