Upgrade waf to 0.9.7-fc95bab69065dbc43ddd71d4b69d0078

Picks up the fix for:
"Make sure to save compiler optimization flags from foo-config scripts

python-config on openSUSE needs -O2 to match -D_FORTIFY_SOURCE"

See https://github.com/waf-project/waf/issues/1886 for additional information

Fixes GitLab issue #215