IMX6 S/DL PXP module

[#1]

  IMX6 S/DL for consumer has both PXP and IPU. Automotive and Industrial
versions doesn't have PXP. As IMX6 also has IPU, the Linux framebuffer driver
uses IPU and not PXP.

Note :

“pxp_v4l2_test.out” from unit_tests was made for processors (i.MX6 SL),

that have only PXP and its framebuffer driver applies PXP to accelerate image
processing.

“pxp_v4l2_test.out” should not be used with i.MX6 S/DL.

To test PXP device with i.MX6 S/DL users have to try “pxp_test.out”.