contrib: flac: simplify .pc patching

dependency on ogg is already specified

contrib/src/flac/libFLAC-pc.patch

---- flac/src/libFLAC/flac.pc.in.orig	2013-05-05 14:05:30.059024229 +0200
-+++ flac/src/libFLAC/flac.pc.in	2013-05-05 14:06:25.529822137 +0200
-@@ -7,6 +7,6 @@
- Description: Free Lossless Audio Codec Library
- Version: @VERSION@
- Requires.private: @OGG_PACKAGE@
--Libs: -L${libdir} -lFLAC
-+Libs: -L${libdir} -lFLAC -logg
- Libs.private: -lm
- Cflags: -I${includedir}

contrib/src/flac/rules.mak

@@ -15,7 +15,6 @@ $(TARBALLS)/flac-$(FLAC_VERSION).tar.xz:
 
 flac: flac-$(FLAC_VERSION).tar.xz .sum-flac
 	$(UNPACK)
-	$(APPLY) $(SRC)/flac/libFLAC-pc.patch
 ifdef HAVE_DARWIN_OS
 	cd $(UNPACK_DIR) && sed -e 's,-dynamiclib,-dynamiclib -arch $(ARCH),' -i.orig configure
 endif
@@ -26,6 +25,7 @@ ifeq ($(ANDROID_ABI), x86)
 	cd $(UNPACK_DIR) && sed -i.orig -e s/"#  undef USE_OBSOLETE_SIGCONTEXT_FLAVOR"/"#define USE_OBSOLETE_SIGCONTEXT_FLAVOR"/g src/libFLAC/cpu.c
 endif
 endif
+	$(call pkg_static,"src/libFLAC/flac.pc.in")
 	$(UPDATE_AUTOCONFIG)
 	$(MOVE)