linux-phytec-fsl

MLK-11133: mtd:gpmi: support runtime pm for gpmi nand

support runtime PM on gpmi nand to save the cost to enable/disable clock
in each NAND IO. The driver also claim high-freq bus when resumed.

Signed-off-by: Han Xu <b45815@freescale.com>
(cherry picked from commit: 5b72b3388d1399420f3b49a0ca937ca5792e2d7d)