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/evb-px5_defconfig b/configs/evb-px5_defconfig
index 1e2b0f0..10586a5 100644
--- a/configs/evb-px5_defconfig
+++ b/configs/evb-px5_defconfig
@@ -32,6 +32,8 @@
 # CONFIG_DISPLAY_CPUINFO is not set
 CONFIG_DISPLAY_BOARDINFO_LATE=y
 CONFIG_ARCH_EARLY_INIT_R=y
+CONFIG_SPL_MAX_SIZE=0x40000
+CONFIG_SPL_PAD_TO=0x7f8000
 CONFIG_SPL_BOOTROM_SUPPORT=y
 # CONFIG_SPL_RAW_IMAGE_SUPPORT is not set
 CONFIG_TPL_SYS_MALLOC_SIMPLE=y
@@ -39,6 +41,7 @@
 CONFIG_SPL_ATF=y
 CONFIG_SPL_ATF_NO_PLATFORM_PARAM=y
 CONFIG_TPL=y
+CONFIG_TPL_MAX_SIZE=0x40000
 CONFIG_CMD_MMC=y
 CONFIG_CMD_CACHE=y
 CONFIG_SPL_OF_CONTROL=y