- Packaging improvements:
* Drop BuildRequires: golang-packaging. The original macros for
file movements into GOPATH are obsolete with Go modules.
* Drop autosetup -n arg only needed when archive and package
name differ
* Remove goprep macro which is no longer recommended
* Remove gobuild macro which is no longer recommended
* Build PIE with pattern that may become recommended procedure:
%%ifnarch ppc64 GOFLAGS="-buildmode=pie" %%endif go build
A go toolchain buildmode default config would be preferable
but none exist at this time.
* Drop mod=vendor, go1.14+ will detect vendor dir and auto-enable
* Remove goinstall macro which is no longer recommended
* Drop defattr(-,root,root) no longer needed with recent rpm (forwarded request 1148283 from jfkw)