Remove RPMTAG_FILESTATUS tag extension

Remove RPMTAG_FILESTATUS tag extension
- This is a bad "API" for verification, it can't be controlled and
  causes heavy IO where one would not expect it. Getting rid of it now
  before anybody starts relying on it...
- Leaving :fstatus format extension alone however, it's at least harmless
  and produces a more predictable output than :vflags extension so it
  might be actually useful in scripts.