libvorbis: Patch to build with clang

packages/libvorbis/configure.patch

@@ -0,0 +1,15 @@
+clang does not support -mno-ieee-fp:
+      https://llvm.org/bugs/show_bug.cgi?id=25615
+
+diff -u -r ../libvorbis-1.3.5/configure ./configure
+--- ../libvorbis-1.3.5/configure	2015-02-26 23:09:49.000000000 +0100
++++ ./configure	2017-01-22 23:48:11.744025641 +0100
+@@ -12685,7 +12685,7 @@
+ 	case $host in
+ 	*86-*-linux*)
+ 		DEBUG="-g -Wall -Wextra -D_REENTRANT -D__NO_MATH_INLINES -fsigned-char"
+-		CFLAGS="-O3 -ffast-math -mno-ieee-fp -D_REENTRANT -fsigned-char"
++		CFLAGS="-O3 -ffast-math -D_REENTRANT -fsigned-char"
+ #              	PROFILE="-Wall -Wextra -pg -g -O3 -ffast-math -D_REENTRANT -fsigned-char -fno-inline -static"
+ 		PROFILE="-Wall -Wextra -pg -g -O3 -ffast-math -mno-ieee-fp -D_REENTRANT -fsigned-char -fno-inline"
+