bus: omap_l3_noc: convert target information into a structure

Currently the target instance information is organized indexed by bit
field offset into multiple arrays.

1. We currently have offsets specific to each target associated with each
clock domains are in seperate arrays:

l3_targ_inst_clk1
l3_targ_inst_clk2
l3_targ_inst_clk3

2. Then they are organized per master index in l3_targ.

3. We have names in l3_targ_inst_name as an array to array of strings
corresponding to the above with offsets.

Simplify the same by defining a structure for information containing
both target offset and name. this is then stored in arrays per domain
and organized into an array indexed off domain.

The array is still indexed based on bit field offset.

Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Darren Etheridge <detheridge@ti.com>
Tested-by: Sekhar Nori <nsekhar@ti.com>