Guard dereference of iwPrefix['iw_trans'] and iwPrefix['iw_local']

Ensure that array indices exist before access to avoid PHP interpreter
undefined index warnings.

Patch also includes trivial whitespace fixes to correct codesniff failures.

Change-Id: I87021a358a85eb3adf7a222fbaee70623dfd8770
Merge "Guard dereference of iwPrefix['iw_trans'] and iwPrefix['iw_local']"