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/dreamplug_defconfig b/configs/dreamplug_defconfig
index 80be9b8..d6b5563 100644
--- a/configs/dreamplug_defconfig
+++ b/configs/dreamplug_defconfig
@@ -50,6 +50,7 @@
 CONFIG_SYS_ATA_DATA_OFFSET=0x100
 CONFIG_SYS_ATA_REG_OFFSET=0x100
 CONFIG_SYS_ATA_ALT_OFFSET=0x100
+CONFIG_LBA48=y
 # CONFIG_MMC is not set
 CONFIG_MTD=y
 CONFIG_DM_SPI_FLASH=y