package/ffmpeg: remove optional dependency to opencv3

OpenCV3 is unmaintained and will be removed from buildroot.

Signed-off-by: Bernd Kuhls <bernd@kuhls.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/ffmpeg/ffmpeg.mk

@@ -297,12 +297,9 @@ else
 FFMPEG_CONF_OPTS += --disable-mmal --disable-omx --disable-omx-rpi
 endif
 
-ifeq ($(BR2_PACKAGE_OPENCV3_LIB_IMGPROC),y)
-FFMPEG_CONF_OPTS += --enable-libopencv
-FFMPEG_DEPENDENCIES += opencv3
 # To avoid a circular dependency only use opencv if opencv itself does
 # not depend on ffmpeg.
-else ifeq ($(BR2_PACKAGE_OPENCV4_LIB_IMGPROC)x$(BR2_PACKAGE_OPENCV4_WITH_FFMPEG),yx)
+ifeq ($(BR2_PACKAGE_OPENCV4_LIB_IMGPROC)x$(BR2_PACKAGE_OPENCV4_WITH_FFMPEG),yx)
 FFMPEG_CONF_OPTS += --enable-libopencv \
 	--extra-cflags=-I$(STAGING_DIR)/usr/include/opencv4
 FFMPEG_DEPENDENCIES += opencv4