Rename the UKI to a mixed case file name with a boot counter before
selecting the first profile, and give the second profile a mixed case
ID, so that both are only reachable if systemd-boot folds the entry IDs
of Type #2 entries with boot counter and of secondary profiles.
The entry IDs passed to bootctl set-default are spelled lower case and
without the counter, like loader.conf(5) documents and bootctl list
shows them.
(cherry picked from commit 3937823293)
(cherry picked from commit e5197414d9)
(cherry picked from commit 9f08873145)