Additionally pull up following revision(s) (requested by maya in ticket #892):

tests/lib/libc/gen/posix_spawn/t_spawnattr.c: revision 1.2,1.3

Don't use SCHED_OTHER.

Fix broken test: we can't assume that the current schedule priority range
will overlap with the requested scheduler range, so get the new scheduler
range, and then try to find a different priority. If that fails (to find
a different scheduling range), give up here.

(martin)