add .pc files for vorbis target

deps/vorbis/lib/pkgconfig/vorbis.pc

@@ -0,0 +1,15 @@
+# libvorbis pkg-config source file
+
+prefix=
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include
+
+Name: vorbis
+Description: vorbis is the primary Ogg Vorbis library
+Version: 1.3.7
+Requires.private: ogg
+Conflicts:
+Libs: -L${libdir} -lvorbis  -logg
+Libs.private: -lm
+Cflags: -I${includedir}

deps/vorbis/lib/pkgconfig/vorbisenc.pc

@@ -0,0 +1,14 @@
+# libvorbisenc pkg-config source file
+
+prefix=
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include
+
+Name: vorbisenc
+Description: vorbisenc is a library that provides a convenient API for setting up an encoding environment using libvorbis
+Version: 1.3.7
+Requires.private: vorbis
+Conflicts:
+Libs: -L${libdir} -lvorbisenc -lvorbis -logg
+Cflags: -I${includedir}

deps/vorbis/lib/pkgconfig/vorbisfile.pc

@@ -0,0 +1,14 @@
+# libvorbisfile pkg-config source file
+
+prefix=
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include
+
+Name: vorbisfile
+Description: vorbisfile is a library that provides a convenient high-level API for decoding and basic manipulation of all Vorbis I audio streams
+Version: 1.3.7
+Requires.private: vorbis
+Conflicts:
+Libs: -L${libdir} -lvorbisfile -lvorbis -logg
+Cflags: -I${includedir}