post: Migrate to Kconfig

We move the existing CONFIG_POST_* functionality over to CFG_POST and
then introduce CONFIG_POST to Kconfig.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/powerpc/cpu/mpc85xx/cpu.c b/arch/powerpc/cpu/mpc85xx/cpu.c
index 74ad748..be85c54 100644
--- a/arch/powerpc/cpu/mpc85xx/cpu.c
+++ b/arch/powerpc/cpu/mpc85xx/cpu.c
@@ -486,7 +486,7 @@
 #endif /* CONFIG_SYS_RAMBOOT */
 #endif
 
-#if CONFIG_POST & CFG_SYS_POST_MEMORY
+#if CFG_POST & CFG_SYS_POST_MEMORY
 
 /* Board-specific functions defined in each board's ddr.c */
 void fsl_ddr_get_spd(generic_spd_eeprom_t *ctrl_dimms_spd,