The _manage_uefi code has a check where it attempts to just
identify the precise partition number of the device, in order
for configuration to be parsed and passed. However, the same code
did not handle the existence of a `p1` partition instead of just a
partition #1. This is because the device naming format is different
with NVMe and Software RAID.
Likely, this wasn't an issue with software raid due to how complex the
code interaction is, but the docs also indicate to use only whole disk
images in that case.
This patch was pulled down my one RH's professional services folks
who has confirmed it does indeed fix the issue at hand. This is noted
as a public comment on the Red Hat bugzilla.
(cherry picked from commit fe825fa97ed1f3c9fa8b1461b63ab133fec20b72)