ENGR00220776 mx6dl_arm2: ECSPI pin config overlaped by epdc

ENGR00220776 mx6dl_arm2: ECSPI pin config overlaped by epdc

ECSPI pin MX6DL_PAD_EIM_D17__ECSPI1_MISO is configured overlap by epdc
MX6DL_PAD_EIM_D17__GPIO_3_17, so that SPI-NOR flash can't work normally.
From schematic of ARM2 board, epdc and spi share this pin if plug epdc
daughter board. But SPI-NOR is on ARM2 mother board, so it should be config
well firstly. So we make sure SPI-NOR work successfully by default. But if
enable epdc , SPI-NOR on ARM2 will work fail.

Signed-off-by: Robin Gong <B38343@freescale.com>