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/mx6cuboxi_defconfig b/configs/mx6cuboxi_defconfig
index edfa8b6..1f15287 100644
--- a/configs/mx6cuboxi_defconfig
+++ b/configs/mx6cuboxi_defconfig
@@ -56,6 +56,7 @@
 CONFIG_SPL_DM=y
 CONFIG_BOUNCE_BUFFER=y
 CONFIG_DWC_AHSATA=y
+CONFIG_LBA48=y
 CONFIG_SPL_SYS_I2C_LEGACY=y
 CONFIG_FSL_USDHC=y
 CONFIG_PHYLIB=y