armv8/fsl-lsch3: Update early MMU table

During booting, IFC is mapped to low region. After booting up, IFC is
remapped to high region for larger space. The environmental variables are
also stored at high region. In order to read the variables during booting,
a virtual mapping is required.

Cache was enabled for entire IFC space before. Actually the first two
entries are big enough (4MB) to cover the boot code and environmental
variables. Remove extra entries. Move OCRAM entry out of ifdef.

Signed-off-by: York Sun <yorksun@freescale.com>