Update palmetto/habanero/firestone config flags.

    -Set BMC_AST2400 in config files to enable serial console
     and to enable SIO boot config functions

RTC:118752
diff --git a/openpower/configs/hostboot/palmetto.config b/openpower/configs/hostboot/palmetto.config
index 12ebc2c..bcd2e59 100755
--- a/openpower/configs/hostboot/palmetto.config
+++ b/openpower/configs/hostboot/palmetto.config
@@ -34,7 +34,7 @@
 
 # turn on console output
 set CONSOLE
-set CONSOLE_AST2400
+set BMC_AST2400
 
 set PNOR_IS_32MB