mtd: nand: Fix length bug in ioread16_rep() and iowrite16_rep()

mtd: nand: Fix length bug in ioread16_rep() and iowrite16_rep()

The ioread16_rep() and iowrite16_rep() implementations are U-Boot specific
and have been introduced with the Linux MTD v3.14 sync. While introducing
these functions, the length for the loop has been miscalculated. The ">> 1"
is already present in the caller. So lets remove it in the function.

Tested on omap3_ha.

Signed-off-by: Stefan Roese <[email protected]>
Cc: Heiko Schocher <[email protected]>
Cc: Tom Rini <[email protected]>
Cc: Scott Wood <[email protected]>
Acked-by: Heiko Schocher <[email protected]>