global: Migrate CONFIG_SYS_I2C_DIRECT_BUS to CFG

Perform a simple rename of CONFIG_SYS_I2C_DIRECT_BUS to CFG_SYS_I2C_DIRECT_BUS

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/README b/README
index a9b225e..fe571f7 100644
--- a/README
+++ b/README
@@ -843,7 +843,7 @@
 		CFG_SYS_NUM_I2C_BUSES
 		Hold the number of i2c buses you want to use.
 
-		CONFIG_SYS_I2C_DIRECT_BUS
+		CFG_SYS_I2C_DIRECT_BUS
 		define this, if you don't use i2c muxes on your hardware.
 		if CFG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
 		omit this define.
@@ -855,7 +855,7 @@
 
 		CFG_SYS_I2C_BUSES
 		hold a list of buses you want to use, only used if
-		CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
+		CFG_SYS_I2C_DIRECT_BUS is not defined, for example
 		a board with CFG_SYS_I2C_MAX_HOPS = 1 and
 		CFG_SYS_NUM_I2C_BUSES = 9: