include stdint.h for int32_t/uint32_t

Signed-off-by: Jussi Kukkonen <jussi.kukkonen@intel.com>
Reviewed-by: Yong Bakos <ybakos@humanoriented.com>
diff --git a/libweston/gl-renderer.c b/libweston/gl-renderer.c
index be6b11e..ed44c6d 100644
--- a/libweston/gl-renderer.c
+++ b/libweston/gl-renderer.c
@@ -30,6 +30,7 @@
 #include <GLES2/gl2ext.h>
 
 #include <stdbool.h>
+#include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>