x264: fix typo in variable name

Fixes:

  http://autobuild.buildroot.org/results/d37/d37856be02bdff5711fc5d6fb1f3d4614fe5fed3/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/x264/x264.mk

@@ -13,7 +13,7 @@ X264_LICENSE_FILES = COPYING
 X264_INSTALL_STAGING = YES
 
 ifeq ($(BR2_i386)$(BR2_x86_64),y)
-	FFMPEG_DEPENDENCIES += host-yasm
+	X264_DEPENDENCIES += host-yasm
 else
 	X264_CONF_OPTS += --disable-asm
 endif