P9-XIP: p9_xip_get_item() can now deal with array attributes
P9-XIP: p9_xip_get_item() can now deal with array attributes

This is a new API only used in one place so far. So enhancing it
should be ok. The funtionality is needed for a p9_xip_tool change.

Change-Id: Ibecb2ee45dc5fbf1394fcac0bfef92aa10468927
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/29752
Reviewed-by: Shakeeb A. Pasha B K <5990c9513e2a0d55088e1d9d279da9933204e66f@in.ibm.com>
Reviewed-by: Sachin Gupta <285b19a698aa558fba6ab25cf25b393d072fd749@in.ibm.com>
Tested-by: Jenkins Server <8e3f934e4c44875bc48d33da3ea13d93ba9a233f@us.ibm.com>
Tested-by: PPE CI <dc75934ba5befb9221434e67a247b93aec46b36b@us.ibm.com>
Tested-by: Hostboot CI <52521565bd8ea18a2b112942dce4f4220a97c2c8@us.ibm.com>
Reviewed-by: Richard J. Knight <94c04f3910596886be97211d492ad29f0ba29cd5@us.ibm.com>
Reviewed-by: Martin Peschke <4c516a35580133f593dfe866810ac6bfbd5b0dba@de.ibm.com>

open-power/hostboot,open-power/hostboot,open-power/hostboot,open-power/hostboot,open-power/hostboot