Convert CONFIG_LBA48 et al to Kconfig

This converts the following to Kconfig:
   CONFIG_LBA48
   CONFIG_SYS_64BIT_LBA

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/sheevaplug_defconfig b/configs/sheevaplug_defconfig
index d014b2a..fa1e7bd 100644
--- a/configs/sheevaplug_defconfig
+++ b/configs/sheevaplug_defconfig
@@ -53,6 +53,8 @@
 CONFIG_DM=y
 CONFIG_SATA_MV=y
 CONFIG_SYS_SATA_MAX_DEVICE=2
+CONFIG_LBA48=y
+CONFIG_SYS_64BIT_LBA=y
 CONFIG_MVEBU_MMC=y
 CONFIG_MTD=y
 CONFIG_MTD_RAW_NAND=y