open_posix_testsuite/.../pthread_spin_trylock: Fix.

* Fix ordering 'volatile static' vs 'static volatile'

* Silence unused warning

Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
open_posix_testsuite/.../sigaltstack: Fix.

* Remove unused variable

* Silence unused warnings

* Remove useless casts

Signed-off-by: Cyril Hrubis <chrubis@suse.cz>