[rhel] Rename rust-srpm-macros to rust-toolset-srpm-macros
The upgrade path was broken because the Rust version compares less than
the rust2rpm-based package version that was in RHEL 8 and 9. With a new
name and appropriate Obsoletes and Provides, it should upgrade cleanly.
Ref: https://issues.redhat.com/browse/RHEL-30636