OMAP4: hwmod: Replace module & device offsets by absolute clkctrl address

Accessing the clkctrl register using offset of module & device is hard
to do in OMAP4 due to the way the CM1, CM2, PRM and PRCM_MPU are located
in the address space. There is no common base address anymore for all the
CM registers.
The easiest way to handle that on OMAP4 is to provide the absolute address
of the XXX_CLKCTRL register per hwmod.

Signed-off-by: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Rajendra Nayak <rnayak@ti.com>