Moved conditional compile into Makefile

Signed-off-by: Andreas Engel <andreas.engel@ericsson.com>
diff --git a/README b/README
index ec164ad..2cdb268 100644
--- a/README
+++ b/README
@@ -380,11 +380,11 @@
 		param header, the default value is zero if undefined.
 
 - Serial Ports:
-		CFG_PL010_SERIAL
+		CONFIG_PL010_SERIAL
 
 		Define this if you want support for Amba PrimeCell PL010 UARTs.
 
-		CFG_PL011_SERIAL
+		CONFIG_PL011_SERIAL
 
 		Define this if you want support for Amba PrimeCell PL011 UARTs.