When we updated main.c to use the same entry points as tor_api.h, we
didn't update ntmain.c. This led to bugs as the two got out of
sync.
There are two calls that we drop in this patch: first, I drop the
call to set_main_thread(), since that's redundant with the init
function in compat_winthreads.c (but see #32884). Second, I drop
the check for CMD_RUN_TOR: I'll add that back with a subsequent
commit.
Closes ticket 32883.
