libGL: fix patch.

srcpkgs/libGL/patches/musl.patch

@@ -20,9 +20,9 @@
  #define MAXTHREADS 1
  
  struct threadpool {
---- src/util/rand_xor.c.orig	2017-05-10 20:12:01.842040501 +0200
-+++ src/util/rand_xor.c	2017-05-10 20:13:30.818969670 +0200
-@@ -23,8 +23,11 @@
+--- src/util/rand_xor.c.orig	2017-06-20 00:38:57.199474067 +0200
++++ src/util/rand_xor.c	2017-06-20 00:40:31.351279557 +0200
+@@ -23,7 +23,9 @@
   */
  
  #if defined(__linux__)
@@ -30,7 +30,5 @@
  #include <sys/file.h>
 +#include <sys/stat.h>
  #include <unistd.h>
-+#include <fcntl.h>
+ #include <fcntl.h>
  #else
- #include <time.h>
- #endif