driver/ifc:Change accessor function to take care of endianness

IFC registers can be of type Little Endian or big Endian depending upon
Freescale SoC. Here SoC defines the register type of IFC IP.

So update acessor functions with common IFC acessor functions to take care
both type of endianness.

Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Acked-by: York Sun <yorksun@freescale.com>
diff --git a/README b/README
index 176de61..6cdf355 100644
--- a/README
+++ b/README
@@ -472,6 +472,12 @@
 		Board config to use DDR3. It can be enabled for SoCs with
 		Freescale DDR3 controllers.
 
+		CONFIG_SYS_FSL_IFC_BE
+		Defines the IFC controller register space as Big Endian
+
+		CONFIG_SYS_FSL_IFC_LE
+		Defines the IFC controller register space as Little Endian
+
 		CONFIG_SYS_FSL_PBL_PBI
 		It enables addition of RCW (Power on reset configuration) in built image.
 		Please refer doc/README.pblimage for more details