[gdk-pixbuf] gif: Fix build on Solaris by including <string.h>

[Emmanuele Bassi <ebassi src gnome org>]

commit 38006d48e001ef56091c83ed4cca58b3eca80d1a
Author: Alan Coopersmith <alan coopersmith oracle com>
Date:   Sun Sep 8 17:50:55 2019 -0700

    gif: Fix build on Solaris by including <string.h>
    
    Fixes build failure of:
    
    ../gdk-pixbuf/io-gif-animation.c: In function ‘gdk_pixbuf_gif_anim_iter_get_pixbuf’:
    ../gdk-pixbuf/io-gif-animation.c:418:17: error: implicit declaration of function ‘memset’ 
[-Werror=implicit-function-declaration]
      418 |                 memset (gdk_pixbuf_get_pixels (anim->last_frame_data), 0, 
gdk_pixbuf_get_rowstride (anim->last_frame_data) * anim->height);
          |                 ^~~~~~
    ../gdk-pixbuf/io-gif-animation.c:418:17: warning: incompatible implicit declaration of built-in function 
‘memset’
    ../gdk-pixbuf/io-gif-animation.c:28:1: note: include ‘<string.h>’ or provide a declaration of ‘memset’
       27 | #include "lzw.h"
      +++ |+#include <string.h>
       28 |
    ../gdk-pixbuf/io-gif-animation.c:443:33: warning: incompatible implicit declaration of built-in function 
‘memset’
      443 |                                 memset (line, 0, (x_end - anim->last_frame->x_offset) * 4);
          |                                 ^~~~~~
    ../gdk-pixbuf/io-gif-animation.c:443:33: note: include ‘<string.h>’ or provide a declaration of ‘memset’
    cc1: some warnings being treated as errors
    
    Signed-off-by: Alan Coopersmith <alan coopersmith oracle com>

 gdk-pixbuf/io-gif-animation.c | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/gdk-pixbuf/io-gif-animation.c b/gdk-pixbuf/io-gif-animation.c
index a3155e065..c9db3c66e 100644
--- a/gdk-pixbuf/io-gif-animation.c
+++ b/gdk-pixbuf/io-gif-animation.c
@@ -21,6 +21,7 @@
  */
 
 #include "config.h"
+#include <string.h>
 #include <errno.h>
 #include "gdk-pixbuf-transform.h"
 #include "io-gif-animation.h"