games/punchy: respect MAKE_JOBS_NUMBER

Pass -j<n> from Cargo to Ninja. NUM_JOBS is part of default variables.
https://doc.rust-lang.org/cargo/reference/environment-variables.html

PR: 293314
Reported by: fuz
Obtained from: upstream

(cherry picked from commit b1c3c8e30d1289957594afbf327de479cc131145)