Correctly implement:

commit c0ec9918b0
	Author: Måns Rullgård <mans@mansr.com>
	Date:   Tue Aug 24 17:47:05 2010 +0000
	Remove global mm_flags variable

	Originally committed as revision 24909 to svn://svn.ffmpeg.org/ffmpeg/trunk

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/dsputil.h

@@ -637,7 +637,11 @@ static inline void emms(void)
     __asm__ volatile ("emms;":::"memory");
 }
 
-#define emms_c() emms()
+#define emms_c() \
+{\
+    if(av_get_cpu_flags() & AV_CPU_FLAG_MMX)\
+        emms();\
+}
 
 #elif ARCH_ARM