linux-arm: enable link time optimization globally

Summary:
Main commit for the global link time optimization patchset.

Depends on D236
Depends on D237
Depends on D238
Depends on D239
Depends on D240
Depends on D241

Test Plan: apply all patches and win

Reviewers: randall.rushing, Mustaavalkosta, Roach, rlasalle15

Differential Revision: http://review.codefirex.com/D242

Change-Id: I8ac184793a46b6f324d26c0de2c763868b144748