refactor vesa mode setting code and bootsplash code

- adds possibility to set a vesa mode without showing a bootsplash
- make bootsplash / mode setting code available in real mode.

Change-Id: I0045c9d75757657f4ce531889593102ea1e39ce5
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/256
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marcj303@gmail.com>

src/lib/fallback_boot.c

@@ -28,7 +28,7 @@ void set_boot_successful(void)
 
 void boot_successful(void)
 {
-#if CONFIG_BOOTSPLASH && !CONFIG_COREBOOT_KEEP_FRAMEBUFFER
+#if CONFIG_FRAMEBUFFER_SET_VESA_MODE && !CONFIG_FRAMEBUFFER_KEEP_VESA_MODE
 	void vbe_textmode_console(void);
 
 	vbe_textmode_console();