installcheck doesn't process the singlespec macros

[lkocman]

Raised by @dirkmueller

https://build.opensuse.org/package/view_file/home:repo-checker/reports/openSUSE:Backports:SLE-15-SP6:Staging:adi:21
, it appears there is a bug in the scanner.

Error: missing alternative provides for python3-olefile
python-olefile is still a build requirement of:

• azote
• chocolate-doom
• crispy-doom
• nml
• openQA

this is because it doesn't process the singlespec macros. actually
python-olefile as buildrequires is being rewritten into
python3-olefile, which is provided in the staging. any chance that we
can fix this issue? otherwise we're not going to get the staging
green.

[nilxam]

the description is not exactly correct, checker evaluating the deleterequests separately, checker doesn't know "renaming" thing at all.

Manually go thru the "renaming" cases is needed.