gitlab: disable optimization and debug symbols in msys build

Building at -O2, adds 33% to the build time, over -O2. IOW a build that
takes 45 minutes at -O0, takes 60 minutes at -O2. Turning off debug
symbols drops it further, down to 38 minutes.

IOW, a "-O2 -g" build is 58% slower than a "-O0" build on msys in the
gitlab CI windows shared runners.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230801130403.164060-8-berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
1 file changed