ENGR00223027 Add support for nand on MFG for IMX6Q

Add support for nand flash on IMX6Q. Modifying partitions number and size.
mx6q_sabreauto_nand_boot.h --> Modify the size of partitions used to 3.
      PARTITION 0 (16M)
------------------------------
|                             |
|             uboot           |
|                             |
------------------------------

      PARTITION 1 (16M)
------------------------------
|                             |
|            Kernel           |
|                             |
------------------------------

      PARTITION 2 (128M)
------------------------------
|                             |
|                             |
|       Root file system      |
|                             |
|                             |
------------------------------

mx6q_sabreauto_mfg_enable_nand.h --> Enable partitions on manufacturing tool

Signed-off-by: Alejandro Sierra <b18039@freescale.com>