gnu: grub: Add patch to fix new version of freetype

* gnu/packages/patches/grub-freetype.patch: New file.
* gnu-system.am (dist_patch_DATA): Add the patch.
* gnu/packages/grub.scm (grub): Apply new patch.

gnu-system.am

@@ -412,6 +412,7 @@ dist_patch_DATA =						\
   gnu/packages/patches/gobject-introspection-girepository.patch	\
   gnu/packages/patches/grep-CVE-2015-1345.patch			\
   gnu/packages/patches/grub-gets-undeclared.patch		\
+  gnu/packages/patches/grub-freetype.patch			\
   gnu/packages/patches/gstreamer-0.10-bison3.patch		\
   gnu/packages/patches/gstreamer-0.10-silly-test.patch		\
   gnu/packages/patches/guile-1.8-cpp-4.5.patch			\

gnu/packages/grub.scm

@@ -79,7 +79,8 @@ (define-public grub
              (sha256
               (base32
                "0n64hpmsccvicagvr0c6v0kgp2yw0kgnd3jvsyd26cnwgs7c6kkq"))
-             (patches (list (search-patch "grub-gets-undeclared.patch")))))
+             (patches (list (search-patch "grub-gets-undeclared.patch")
+                            (search-patch "grub-freetype.patch")))))
     (build-system gnu-build-system)
     (arguments
      '(#:configure-flags '("--disable-werror")

gnu/packages/patches/grub-freetype.patch

+commit fd0df6d098b1e6a4f60275c48a3ec88d15ba1fbb
+Author: Colin Watson <cjwatson@ubuntu.com>
+Date:   Fri Nov 29 12:19:36 2013 +0000
+
+    Fix build with FreeType 2.5.1
+    
+    * util/grub-gen-asciih.c: Include FT_SYNTHESIS_H rather than
+    <freetype/ftsynth.h>, fixing build with FreeType 2.5.1.
+    * util/grub-gen-widthspec.c: Likewise.
+    * util/grub-mkfont.c: Likewise.
+
+diff --git a/util/grub-mkfont.c b/util/grub-mkfont.c
+index 0d8eb78..242dd01 100644
+--- a/util/grub-mkfont.c
++++ b/util/grub-mkfont.c
+@@ -43,7 +43,7 @@
+ #include FT_FREETYPE_H
+ #include FT_TRUETYPE_TAGS_H
+ #include FT_TRUETYPE_TABLES_H
+-#include <freetype/ftsynth.h>
++#include FT_SYNTHESIS_H
+ 
+ #undef __FTERRORS_H__
+ #define FT_ERROR_START_LIST   const char *ft_errmsgs[] = {