powerpc/P1010: Add workaround for erratum P1010-A003549 (related to IFC)

Issue:
Peripheral connected to IFC_CS3 may hamper booting from IFC.

Impact:
Boot from IFC may not be successful if IFC_CS3 is used.

Workaround:
If IFC_CS3 is used, gate IFC_CS3 while booting from NAND or NOR.
Also Software should select IFC_CS3 using PMUXCR[26:27] = 0x01.

Signed-off-by: Poonam Aggrwal <poonam.aggrwal@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>