MGS-504 imx: i.MX6DL gpu3d_core_clk should be 528M instead of 396M

MGS-504 imx: i.MX6DL gpu3d_core_clk should be 528M instead of 396M

This patch is refined from the previous commit 20d89c9c909:

-Update the parent of gpu2d_core for mx6dl.
-Update the parent of gpu3d_shader and gpu3d_core for mx6dl.
-Update the clock of gpu3d_shader and gpu3d_core for mx6dl.
The code change is cherry-picked from patch 00e75bcba16d.

Signed-off-by: Loren Huang <b02279@freescale.com>
Signed-off-by: Xianzhong <b07117@freescale.com>
Acked-by: Jason Liu
(cherry picked from commit e63222bdba7c2de063c6367017ccd6a1d1d3cc22)