Convert CONFIG_SPL_PAD_TO et al to Kconfig

This converts the following to Kconfig:
   CONFIG_SPL_PAD_TO
   CONFIG_SPL_MAX_SIZE
   CONFIG_TPL_PAD_TO
   CONFIG_TPL_MAX_SIZE

Note that we need to make TPL_MAX_SIZE be hex, and so move and convert the
existing places.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/ls1043aqds_nand_defconfig b/configs/ls1043aqds_nand_defconfig
index 04e3413..079cbb3 100644
--- a/configs/ls1043aqds_nand_defconfig
+++ b/configs/ls1043aqds_nand_defconfig
@@ -45,6 +45,8 @@
 # CONFIG_USE_BOOTCOMMAND is not set
 CONFIG_ARCH_MISC_INIT=y
 CONFIG_MISC_INIT_R=y
+CONFIG_SPL_MAX_SIZE=0x1a000
+CONFIG_SPL_PAD_TO=0x20000
 CONFIG_SPL_FSL_PBL=y
 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR=y
 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR=0xf0