x86/emms: empty the mmx state unconditionally on supported targets

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>

libavutil/x86/emms.h

@@ -34,7 +34,13 @@ void avpriv_emms_yasm(void);
  */
 static av_always_inline void emms_c(void)
 {
+/* Some inlined functions may also use mmx instructions regardless of
+ * runtime cpuflags. With that in mind, we unconditionally empty the
+ * mmx state if the target cpu chosen at configure time supports it.
+ */
+#if !defined(__MMX__)
     if(av_get_cpu_flags() & AV_CPU_FLAG_MMX)
+#endif
         __asm__ volatile ("emms" ::: "memory");
 }
 #elif HAVE_MMX && HAVE_MM_EMPTY