wait_for_scan_result takes lists of ssids/bsses

All of the other scan functions in the iw_runner take a list
of ssids of bsses.  This make wait_for_scan_result consistent
with the rest of the scan methods.

TEST=unittest
BUG=None

Change-Id: I43bff12c79259cdcb3584b0bd056fd4df2708cc6
Reviewed-on: https://chromium-review.googlesource.com/276347
Tested-by: Kris Rambish <krisr@chromium.org>
Reviewed-by: Christopher Wiley <wiley@chromium.org>
Commit-Queue: Kris Rambish <krisr@chromium.org>
Trybot-Ready: Kris Rambish <krisr@chromium.org>
4 files changed