package/ffmpeg: default to --cpu=generic for MIPS architecture

This option is needed to prevent this message from configure:

WARNING: unknown CPU. Disabling all MIPS optimizations.

Signed-off-by: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
[Thomas:
 - group with the other --cpu conditions so that only one is passed.
 - improve the comment.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/ffmpeg/ffmpeg.mk

@@ -449,12 +449,17 @@ else
 FFMPEG_CONF_OPTS += --disable-pic
 endif
 
-ifneq ($(call qstrip,$(BR2_GCC_TARGET_CPU)),)
+# Default to --cpu=generic for MIPS architecture, in order to avoid a
+# warning from ffmpeg's configure script.
+ifeq ($(BR2_mips)$(BR2_mipsel)$(BR2_mips64)$(BR2_mips64el),y)
+FFMPEG_CONF_OPTS += --cpu=generic
+else ifneq ($(call qstrip,$(BR2_GCC_TARGET_CPU)),)
 FFMPEG_CONF_OPTS += --cpu=$(BR2_GCC_TARGET_CPU)
 else ifneq ($(call qstrip,$(BR2_GCC_TARGET_ARCH)),)
 FFMPEG_CONF_OPTS += --cpu=$(BR2_GCC_TARGET_ARCH)
 endif
 
+
 FFMPEG_CONF_OPTS += $(call qstrip,$(BR2_PACKAGE_FFMPEG_EXTRACONF))
 
 # Override FFMPEG_CONFIGURE_CMDS: FFmpeg does not support --target and others