sdhci-of: Fix the wrong accessor to HOSTVER register

Freescale eSDHC controller has the special order for
the HOST version register. that is not same as the other's
registers. The address of HOSTVER in spec is 0xFE, and
we need use the in_be16(0xFE) to access it, not in_be16(0xFC).

Signed-off-by: Dave Liu <daveliu@freescale.com>
Acked-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>