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/ls1021aqds_sdcard_qspi_defconfig b/configs/ls1021aqds_sdcard_qspi_defconfig
index 230f147..ad03479 100644
--- a/configs/ls1021aqds_sdcard_qspi_defconfig
+++ b/configs/ls1021aqds_sdcard_qspi_defconfig
@@ -39,6 +39,8 @@
 CONFIG_ARCH_MISC_INIT=y
 CONFIG_MISC_INIT_R=y
 CONFIG_ID_EEPROM=y
+CONFIG_SPL_MAX_SIZE=0x1a000
+CONFIG_SPL_PAD_TO=0x1c000
 CONFIG_SPL_FSL_PBL=y
 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR=y
 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR=0xe8