package/opkg-utils: drop host-diffutils dependency

diffutils is now a host system dependency, so there is no need for
opkg-utils to depend on host-diffutils.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/opkg-utils/opkg-utils.mk

@@ -12,7 +12,6 @@ OPKG_UTILS_LICENSE_FILES = COPYING
 
 HOST_OPKG_UTILS_DEPENDENCIES = \
 	$(BR2_PYTHON3_HOST_DEPENDENCY) \
-	host-diffutils \
 	host-lz4 \
 	host-xz