[mutter] egl: Fix GCC warning

[Bastien Nocera <hadess src gnome org>]

commit 9b64e09a24643264a537970572deaabe1c1098b7
Author: Bastien Nocera <hadess hadess net>
Date:   Tue Jan 17 14:21:23 2017 +0100

    egl: Fix GCC warning
    
    src/backends/meta-egl.c: In function ‘set_egl_error’:
    src/backends/meta-egl.c:144:16: error: format not a string literal and no format arguments 
[-Werror=format-security]
          error_str);
          ^~~~~~~~~
    
    https://bugzilla.gnome.org/show_bug.cgi?id=777389

 src/backends/meta-egl.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/src/backends/meta-egl.c b/src/backends/meta-egl.c
index 7e75d86..258f5be 100644
--- a/src/backends/meta-egl.c
+++ b/src/backends/meta-egl.c
@@ -139,9 +139,9 @@ set_egl_error (GError **error)
     return;
 
   error_str = get_egl_error_str ();
-  g_set_error (error, G_IO_ERROR,
-               G_IO_ERROR_FAILED,
-               error_str);
+  g_set_error_literal (error, G_IO_ERROR,
+                       G_IO_ERROR_FAILED,
+                       error_str);
 }
 
 static gboolean