There are a couple of changes needed:
1. Package version cannot contain '-' (5.4-rc5-1.pvops.qubes is an
invalid rpm version). Follow Fedora upstream idea of moving 'rc' tag
into package release field, as 0.rcXX.(original rel). This way, such
package will be 'older' than the final release (with just release
number there - 1 in most cases). The alternative idea is using
'~rcXX' in the package version, but ~ couldn't be part of a kernel
version reported by the kernel itself and also qubes-dom0-update
refuses ~ in a package filename.
2. Adjust kernel version to match the above - specifically clear
EXTRAVERSION (-rcXX suffix), as it will be added back as package
release (CONFIG_LOCALVERSION).
3. rc tarballs are available only as a git-generated .tar.gz (not
.tar.xz) and there are no matching detached signatures. While it
would be possible to download a signed tag via git, scripting that
would be overly complex as for the task rarely used. Leave this
verification as a manual step and require sha512 checksum to be
committed into repository.
To build an archive matching upstream one, out of a signed tag, use
command like this:
git archive --prefix=linux-5.4-rc5/ --output=../linux-5.4-rc5.tar.gz v5.4-rc5
While at it, remove obsolete BUILD_FLAVOR variable.
17b7186716