Add valkey package for aarch64 (arm64)

Is your feature request related to a problem? Please describe.

Harbor (CNCF container registry) uses Photon OS as its base image and depends on the valkey package. Currently, tdnf install -y valkey works on x86_64 but fails on aarch64 because the valkey package is not available for that architecture.

This blocks arm64 builds of Harbor's valkey container image. We've had to work around this by compiling valkey from source specifically for arm64, while amd64 continues to use the tdnf package.

Related PR: https://github.com/goharbor/harbor/pull/23282

Describe the solution you'd like

Please build and publish the valkey package (currently at version 9.1.0) for the aarch64 architecture in the Photon OS 5.0 package repository, so that tdnf install -y valkey works on both x86_64 and aarch64.

Describe alternatives you've considered

We are currently compiling valkey from the upstream source tarball (https://github.com/valkey-io/valkey) during the Docker image build as a workaround for arm64. This works but:

• Increases build time (~2 minutes compile vs seconds for package install)
• Loses package provenance and automatic security update flow via tdnf
• Requires maintaining a separate build path per architecture in the Dockerfile
• Shifts CVE/update ownership from the Photon package maintainers to downstream consumers

Once the aarch64 package is available, we can unify back to a single tdnf install -y valkey for all architectures.

Additional context

• Photon OS version: 5.0
• Package: valkey
• Missing architecture: aarch64
• x86_64 package exists and works fine
• Harbor arm64 support PR: https://github.com/goharbor/harbor/pull/23282
• Harbor arm64 multi-arch PR: https://github.com/goharbor/harbor/pull/22311