ARM: dts: OMAP5/DRA7: use omap5-mpu-dpll-clock capable of dealing with higher frequencies

OMAP5432, DRA75x and DRA72x have MPU DPLLs that need Duty Cycle
Correction(DCC) to operate safely at frequencies >= 1.4GHz.

Switch to "ti,omap5-mpu-dpll-clock" compatible property which provides
this support.

Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>