Most, but not all, files in scripts have execute permission. While we
don't need this in order to launch them via meson/ninja build rules,
it is nice to direct execution if they have execution permission. This
makes the practice consistent across all scripts.
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>