at91: Switch to SD_BOOT / CONFIG_NAND_BOOT

The values CONFIG_SYS_USE_NANDFLASH and CONFIG_SYS_USE_MMC serve the
same purpose as CONFIG_SD_BOOT / CONFIG_NAND_BOOT so migrate to using
these switches instead as they're already in Kconfig.

Cc: Stelian Pop <stelian@popies.net>
Cc: Heiko Schocher <hs@denx.de>
Cc: Daniel Gorsulowski <daniel.gorsulowski@esd.eu>
Cc: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/taurus_defconfig b/configs/taurus_defconfig
index 76f902b..68de985 100644
--- a/configs/taurus_defconfig
+++ b/configs/taurus_defconfig
@@ -32,6 +32,7 @@
 CONFIG_SPL_SPI=y
 CONFIG_DEBUG_UART=y
 CONFIG_SYS_LOAD_ADDR=0x22000000
+CONFIG_NAND_BOOT=y
 CONFIG_BOOTDELAY=3
 CONFIG_USE_BOOTARGS=y
 CONFIG_BOOTARGS="console=ttyS0,115200 earlyprintk mtdparts=atmel_nand:256k(bootstrap)ro,512k(uboot)ro,256k(env),256k(env_redundant),256k(spare),512k(dtb),6M(kernel)ro,-(rootfs) root=/dev/mtdblock7 rw rootfstype=jffs2"
@@ -77,7 +78,6 @@
 CONFIG_AT91_GPIO=y
 # CONFIG_MMC is not set
 CONFIG_MTD=y
-CONFIG_MTD_RAW_NAND=y
 # CONFIG_SYS_NAND_USE_FLASH_BBT is not set
 CONFIG_NAND_ATMEL=y
 CONFIG_SYS_NAND_BLOCK_SIZE=0x20000