fontconfig: store font cache in /var/cache/fontconfig, and not in /usr/var/..

package/fontconfig/fontconfig.mk

@@ -15,6 +15,7 @@ FONTCONFIG_CONF_ENV = CFLAGS="-I$(STAGING_DIR)/usr/include/freetype2"
 
 FONTCONFIG_CONF_OPT = --with-arch=$(GNU_TARGET_NAME) \
 		--with-freetype-config="$(STAGING_DIR)/usr/bin/freetype-config" \
+		--with-cache-dir=/var/cache/fontconfig
 		--with-expat="$(STAGING_DIR)/usr/lib" \
 		--with-expat-lib=$(STAGING_DIR)/usr/lib \
 		--with-expat-includes=$(STAGING_DIR)/usr/include \