Convert CONFIG_SPL_BSS_MAX_SIZE et al to Kconfig

This converts the following to Kconfig:
   CONFIG_SPL_BSS_MAX_SIZE
   CONFIG_SPL_MAX_FOOTPRINT

Note that the da850evm platforms were violating the "only use one" rule
here, and so now hard-code their BSS limit.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/ls1046aqds_nand_defconfig b/configs/ls1046aqds_nand_defconfig
index f56f078..065f6d0 100644
--- a/configs/ls1046aqds_nand_defconfig
+++ b/configs/ls1046aqds_nand_defconfig
@@ -47,6 +47,7 @@
 CONFIG_MISC_INIT_R=y
 CONFIG_SPL_MAX_SIZE=0x17000
 CONFIG_SPL_PAD_TO=0x40000
+CONFIG_SPL_BSS_MAX_SIZE=0x80000
 CONFIG_SPL_FSL_PBL=y
 CONFIG_SPL_BOARD_INIT=y
 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_USE_SECTOR=y