configs: at91: Remove CONFIG_SYS_EXTRA_OPTIONS assignment

To remove the assignment of CONFIG_SYS_EXTRA_OPTIONS option,
which is deprecated, use the CONFIG_XXXX_BOOT options to
indicate the boot media, and the SoC is selected by the board.

Signed-off-by: Wenyou Yang <wenyou.yang@microchip.com>
diff --git a/board/atmel/at91sam9m10g45ek/at91sam9m10g45ek.c b/board/atmel/at91sam9m10g45ek/at91sam9m10g45ek.c
index 903732b..98430c4 100644
--- a/board/atmel/at91sam9m10g45ek/at91sam9m10g45ek.c
+++ b/board/atmel/at91sam9m10g45ek/at91sam9m10g45ek.c
@@ -84,9 +84,9 @@
 	at91_set_pio_pullup(AT91_PIO_PORTD, 7, 1);
 	at91_set_pio_pullup(AT91_PIO_PORTD, 8, 1);
 
-#ifdef CONFIG_SYS_USE_MMC
+#ifdef CONFIG_SD_BOOT
 	at91_mci_hw_init();
-#elif CONFIG_SYS_USE_NANDFLASH
+#elif CONFIG_NAND_BOOT
 	at91sam9m10g45ek_nand_hw_init();
 #endif
 }