Factorize some code into the new function ff_toupper4().

Patch by Francesco Lavra, francescolavra interfree it

Originally committed as revision 23158 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/utils.c

@@ -1294,3 +1294,11 @@ int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op))
     }
     return 0;
 }
+
+unsigned int ff_toupper4(unsigned int x)
+{
+    return     toupper( x     &0xFF)
+            + (toupper((x>>8 )&0xFF)<<8 )
+            + (toupper((x>>16)&0xFF)<<16)
+            + (toupper((x>>24)&0xFF)<<24);
+}