Update gyp files to use libchromeos from src/platform2

libchromeos was moved from src/platform to src/platform2. This CL updates
the gyp files to use the new location.

BUG=chromium:370258
TEST=FEATURES=test emerge-amd64-generic platform2
TEST=trybot run on daisy, link, mario and duck

CQ-DEPEND=CL:202334

Change-Id: I3b6cd434c1af92bfadb4a9b3995e9a8b94b86146
Reviewed-on: https://chromium-review.googlesource.com/202395
Reviewed-by: Prathmesh Prabhu <[email protected]>
Tested-by: Bertrand Simonnet <[email protected]>
Commit-Queue: Bertrand Simonnet <[email protected]>
1 file changed