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/r8a77990_ebisu_defconfig b/configs/r8a77990_ebisu_defconfig
index 3fd65e9..a2349c0 100644
--- a/configs/r8a77990_ebisu_defconfig
+++ b/configs/r8a77990_ebisu_defconfig
@@ -24,6 +24,7 @@
 # CONFIG_BOARD_EARLY_INIT_F is not set
 CONFIG_SYS_MALLOC_BOOTPARAMS=y
 CONFIG_UPDATE_TFTP=y
+CONFIG_SPL_BSS_MAX_SIZE=0x1000
 CONFIG_HUSH_PARSER=y
 CONFIG_SYS_MAXARGS=64
 CONFIG_SYS_PBSIZE=2068