libopenmpt: drop pkg-config patch as correct invocation now called from mpd

- mpd: link against static libopenmpt

packages/audio/libopenmpt/patches/libopenmpt-add-libvorbisfile-to-pkgconfig.patch

@@ -1,11 +0,0 @@
---- a/libopenmpt/libopenmpt.pc.in	2016-07-09 18:17:00.000000000 +0000
-+++ b/libopenmpt/libopenmpt.pc.in	2021-12-25 00:53:54.189008995 +0000
-@@ -8,7 +8,7 @@
- Description: Tracker module player based on OpenMPT
- Version: @VERSION@
- Requires.private: @LIBOPENMPT_REQUIRES_PRIVATE@
--Libs: -L${libdir} -lopenmpt
-+Libs: -L${libdir} -lopenmpt -lvorbisfile
- Libs.private: @LIBOPENMPT_LIBS_PRIVATE@
- Cflags: -I${includedir}
-