It never used vesa directly, it passes nomodeset, so make it less
confusing. Also simplify the menu text so that it fits on the screen
for distributions with long names.
anaconda in F34 and Rawhide recently stopped accepting params
without the inst. prefix, so 'rescue' does nothing except print
a warning now. We need to use `inst.rescue`. This has worked for
quite a long time so will be OK at least on all Fedoras and RHEL
8, not sure about RHEL 7.
Signed-off-by: Adam Williamson <awilliam@redhat.com>