libid3tag: don't depend on libmad

libid3tag doesn't use libmad.

package/audio/libid3tag/Config.in

@@ -1,7 +1,6 @@
 config BR2_PACKAGE_LIBID3TAG
 	bool "libid3tag"
 	select BR2_PACKAGE_ZLIB
-	depends on BR2_PACKAGE_LIBMAD
 	help
 	  ID3 tag reading library from the MAD project.
 

package/audio/libid3tag/libid3tag.mk

@@ -46,7 +46,7 @@ $(TARGET_DIR)/$(LIBID3TAG_TARGET_BIN): $(STAGING_DIR)/$(LIBID3TAG_TARGET_BIN)
 	cp -dpf $(STAGING_DIR)/usr/lib/libid3tag.so* $(TARGET_DIR)/usr/lib/
 	-$(STRIPCMD) $(STRIP_STRIP_UNNEEDED) $(TARGET_DIR)/usr/lib/libid3tag.so*
 
-libid3tag: uclibc zlib libmad $(TARGET_DIR)/$(LIBID3TAG_TARGET_BIN)
+libid3tag: uclibc zlib $(TARGET_DIR)/$(LIBID3TAG_TARGET_BIN)
 
 libid3tag-source: $(DL_DIR)/$(LIBID3TAG_SOURCE)