OMAP4: hwmod: Naming of address space

Added a name to address space belonging to SDMA and MPU facilitating
the driver to get the address space info by name. Added a revision
member inorder to facilitate the driver to differentiate between
mcbsp in different omap.
Also added a platform_get_irq in probe to get irq number by index since
from OMAP4, there will be a single irq line.

Signed-off-by: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>