ARM: OMAP5: Add minimal support for OMAP5430 SOC

OMAP5430 is Texas Instrument's SOC based on ARM Cortex-A15 SMP
architecture. It's a dual core SOC with GIC used for interrupt
handling and with an integrated L2 cache controller.

OMAP5432 is another variant of OMAP5430, with a
memory controller supporting DDR3 and SATA.

Patch includes:
 - The machine specific headers and sources updates.
 - Platform header updates.
 - Minimum initialisation support for serial.
 - IO table init

Signed-off-by: R Sricharan <r.sricharan@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>