Remove unused patch from repo

qrencode-fix-LIBPTHREAD-macro.patch

@@ -1,9 +0,0 @@
---- ./libqrencode.pc.in.orig	2012-02-20 15:36:29.983533958 -0800
-+++ ./libqrencode.pc.in	2012-02-20 15:56:41.252501662 -0800
-@@ -6,5 +6,5 @@ includedir=@includedir@
- Name: libqrencode
- Description: A QR Code encoding library
- Version: @VERSION@
--Libs: -L${libdir} -lqrencode @LIBPTHREAD@
-+Libs: -L${libdir} -lqrencode -pthread
- Cflags: -I${includedir}