ozone: drm: Fix gbm build with GN
ERROR at //ui/ozone/platform/drm/BUILD.gn:122:3: Replacing nonempty list.
configs = [ ":libdrm" ]
^------
This overwrites a previously-defined nonempty list (length 15).
See //build/config/BUILDCONFIG.gn:504:13: for previous definition
configs = _native_compiler_configs
^-----------------------
with another one (length 1). Did you mean "+=" to append instead? If you
really want to do this, do
BUG=531814
TEST=gn gen gn_ozone --args='target_os="chromeos" use_ozone=true'
Review URL: https://codereview.chromium.org/
1347863002
Cr-Commit-Position: refs/heads/master@{#349061}