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/P2020RDB-PC_36BIT_NAND_defconfig b/configs/P2020RDB-PC_36BIT_NAND_defconfig
index 487483a..c196489 100644
--- a/configs/P2020RDB-PC_36BIT_NAND_defconfig
+++ b/configs/P2020RDB-PC_36BIT_NAND_defconfig
@@ -76,6 +76,7 @@
 CONFIG_USE_ETHPRIME=y
 CONFIG_ETHPRIME="eTSEC1"
 CONFIG_DM=y
+CONFIG_LBA48=y
 CONFIG_DDR_CLK_FREQ=66666666
 CONFIG_CHIP_SELECTS_PER_CTRL=1
 CONFIG_SYS_BR0_PRELIM_BOOL=y