Add elgext.h header
diff --git a/src/video/vita/SDL_vitagl_c.h b/src/video/vita/SDL_vitagl_c.h
index 61d44e4..9a77d5b 100644
--- a/src/video/vita/SDL_vitagl_c.h
+++ b/src/video/vita/SDL_vitagl_c.h
@@ -25,6 +25,7 @@
#include <pib.h>
#include <EGL/egl.h>
+#include <EGL/eglext.h>
#include <GLES2/gl2.h>
#include <GLES2/gl2ext.h>