databases/valkey: Update to 7.2.5, first stable release of valkey
- Use 'install' target of Makefile in source tree to install binaries.
- Add pkgconfig to USES.
- Enable portscout check.
ReleaseNotes: https://github.com/valkey-io/valkey/blob/7.2.5/00-RELEASENOTES
PR: 278466
Reported by: Mohamed Akram