drivers: bus: omap_l3: Convert to use devm_ioremap_resource()
We can then remove the iounmap() calls from probe and remove.
Since the driver requests the resources via index we can do the mem resource
request within a for loop.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Nishanth Menon <nm@ti.com> Tested-by: Sekhar Nori <nsekhar@ti.com>