ffmpeg: don't force Intel Core 2 optimizations if not building 64-bit on Solaris

Signed-off-by: Rafaël Carré <funman@videolan.org>
(cherry picked from commit 97fc89290b0279c826232b816e5ba5c334283d79)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

contrib/src/ffmpeg/rules.mak

@@ -136,7 +136,10 @@ FFMPEGCONF += --enable-pthreads
 endif
 
 ifdef HAVE_SOLARIS
-FFMPEGCONF += --cpu=core2 --enable-pic
+ifeq ($(ARCH),x86_64)
+FFMPEGCONF += --cpu=core2
+endif
+FFMPEGCONF += --enable-pic
 endif
 
 # Build