Allow codecs that use log2comp (g726) to compile correctly on x86 with gcc4 optimizations.

(closes issue #12253)
Reported by: fossil
Patches:
      log2comp.patch uploaded by fossil (license 140)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@109648 65c4cc65-6c06-0410-ace0-fbb531ad65f3

codecs/log2comp.h

@@ -43,7 +43,7 @@ static inline int ilog2(int val)
 		decl	%0			;\
 		bsrl	%1, %0		;\
 		"
-		: "=r" (a)
+		: "=&r" (a)
 		: "mr" (val)
 		: "cc"
 	);