clk: imx6sl: add mmdc ipg clocks

i.MX6SL has MMDC0 and MMDC1 ipg clock in CCM CCGR, add them into
clock tree for clock management.

Signed-off-by: Anson Huang <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
Signed-off-by: Stephen Boyd <[email protected]>
2 files changed