"fsck/bcachefsck_all:" coming before "all:" in the Makefile
causes the bcachefs binary not being built by default. Fix
this by explicitly setting the .DEFAULT_GOAL=all.
Signed-off-by: Tero Roponen <tero.roponen@gmail.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>