compat-usrmerge-84.87-160000.2.2

- Fix logic for detecting conflicts with directories (boo#1191111)

- exit file triggers early if alread usrmerged

- statically link xmv to avoid glibc 2.34 dependency
  (__libc_start_main@GLIBC_2.34)
- turn on filetriggers in main package. Needed for single transaction upgrades
  (boo#1189788)

- another fix for split /usr to avoid running out of space (boo#1186781)
- unsafe fallback also for ENOSYS on renameat2 as seen on WSL

- early exit in case of overlayfs (boo#1187027)

- Avoid dependency on mountpoint from util-linux
- Also check for availability of find

- fix conversion with split /usr (boo#1186781)

- exit early if one of the affected directories has mountpoint
  beneath it

- add fallback for filesystems without renameat2 (boo#1186637)

- catch boolean deps