Don't use typedefs that hide *s.

gr_surface was causing confusion for no good reason.

Change-Id: If7120187f9a00dd16297877fc49352185a4d4ea6
diff --git a/minui/graphics_fbdev.cpp b/minui/graphics_fbdev.cpp
index 9dbdde8..997e9ca 100644
--- a/minui/graphics_fbdev.cpp
+++ b/minui/graphics_fbdev.cpp
@@ -33,8 +33,8 @@
 #include "minui.h"
 #include "graphics.h"
 
-static gr_surface fbdev_init(minui_backend*);
-static gr_surface fbdev_flip(minui_backend*);
+static GRSurface* fbdev_init(minui_backend*);
+static GRSurface* fbdev_flip(minui_backend*);
 static void fbdev_blank(minui_backend*, bool);
 static void fbdev_exit(minui_backend*);
 
@@ -79,7 +79,7 @@
     displayed_buffer = n;
 }
 
-static gr_surface fbdev_init(minui_backend* backend) {
+static GRSurface* fbdev_init(minui_backend* backend) {
     int fd = open("/dev/graphics/fb0", O_RDWR);
     if (fd == -1) {
         perror("cannot open fb0");
@@ -174,7 +174,7 @@
     return gr_draw;
 }
 
-static gr_surface fbdev_flip(minui_backend* backend __unused) {
+static GRSurface* fbdev_flip(minui_backend* backend __unused) {
     if (double_buffered) {
 #if defined(RECOVERY_BGRA)
         // In case of BGRA, do some byte swapping