Update soong_config_string_variables am: 971feffccb

Original change: https://android-review.googlesource.com/c/platform/frameworks/opt/net/wifi/+/2271973

Change-Id: I566b63c6bdbc717d4f5be7359151334a02215097
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>