imx6: fix GW52xx usbotg select pinmux

GPIO2 is used to select the routing of the USBOTG bus between the
Front Panel connector and the PCIe Socket.  By default we want this
to route to the front panel which this patch achieves.

To route USBOTG to the PCIe socket from Linux, export the GPIO and drive it
high:
  echo 2 > /sys/class/gpio/export
  echo out > /sys/class/gpio/gpio2/direction
  echo 1 > /sys/class/gpio/gpio2/value  ;# high to route to PCIe socket J8
  echo 0 > /sys/class/gpio/gpio2/value  ;# low to route to front panel OTG

Note that when routing USB to the PCIe socket J8 you must have a USBOTG
micro-A cable connected which grounds the ID pin to put the OTG controller
into host mode.  This will not be necessary on revision B+ of the GW52xx as
the grounding of this signal will be done on-board when GPIO2 is driven high
to route USBOTG to J8.
mxs_nand: Fix ECC strength for NAND flash with OOB size of 224

On a board with an i.mx28 and a Micron MT29F4G08ABAEAH4, Linux says:

NAND device: Manufacturer ID: 0x2c, Chip ID: 0xdc (Micron MT29F4G08ABAEAH4),
512MiB, page size: 4096, OOB size: 224) the ECC strength is 16.

root@(none):/sys/devices/virtual/mtd/mtd0# for i in ecc_strength oobsize subpagesize; do echo $i = `cat $i`; done
ecc_strength = 16
oobsize = 224
subpagesize = 4096

The ECC strength was not properly discovered by U-Boot causing the data
written by Linux to return an -74 (EBADMSG) when read from U-Boot. This
patch fixes mxs_nand_get_ecc_strength() to function in case of a NAND
flash with page_data_size = 4096 and page_oob_size= 224.

Signed-off-by: Elie De Brauwer <eliedebrauwer@gmail.com>
Acked-by: Scott Wood <scottwood@freescale.com>