lint: fix misc warnings

Mostly docstring warnings, but also silence some expected missing imports.

BUG=chromium:431514
TEST=no more lint warnings
TEST=`./cbuildbot/run_tests` passes

Change-Id: Ib474785ffe5e1595cdd52d3a4f455681dfcf44dd
Reviewed-on: https://chromium-review.googlesource.com/236260
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
diff --git a/scripts/fwgdb.py b/scripts/fwgdb.py
index c8e3df9..6216701 100644
--- a/scripts/fwgdb.py
+++ b/scripts/fwgdb.py
@@ -25,8 +25,10 @@
 # Need to do this before Servo import
 cros_build_lib.AssertInsideChroot()
 
+# pylint: disable=import-error
 from servo import client
 from servo import multiservo
+# pylint: enable=import-error
 
 _SRC_ROOT = os.path.join(constants.CHROOT_SOURCE_ROOT, 'src')
 _SRC_DC = os.path.join(_SRC_ROOT, 'platform/depthcharge')