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/mx23evk_defconfig b/configs/mx23evk_defconfig
index a9d7b14..fbd9992 100644
--- a/configs/mx23evk_defconfig
+++ b/configs/mx23evk_defconfig
@@ -22,6 +22,7 @@
 # CONFIG_DISPLAY_BOARDINFO is not set
 CONFIG_ARCH_MISC_INIT=y
 # CONFIG_SPL_FRAMEWORK is not set
+CONFIG_SPL_NO_BSS_LIMIT=y
 CONFIG_SPL_NO_CPU_SUPPORT=y
 CONFIG_HUSH_PARSER=y
 CONFIG_SYS_MAXARGS=32