Convert CONFIG_ATMEL_LCD et al to Kconfig

This converts the following to Kconfig:
   CONFIG_ATMEL_LCD
   CONFIG_ATMEL_LCD_BGR555
   CONFIG_ATMEL_LCD_RGB565
   CONFIG_GURNARD_SPLASH

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/at91sam9261ek_nandflash_defconfig b/configs/at91sam9261ek_nandflash_defconfig
index b80d5a6..3294579 100644
--- a/configs/at91sam9261ek_nandflash_defconfig
+++ b/configs/at91sam9261ek_nandflash_defconfig
@@ -62,3 +62,4 @@
 CONFIG_TIMER=y
 CONFIG_ATMEL_PIT_TIMER=y
 CONFIG_USB=y
+CONFIG_ATMEL_LCD_BGR555=y