lib: Add tst_process_state_wait2()

The tst_process_state_wait() uses the tst_brkm() interface and is not
suitable for use in child processes.

This adds similar tst_process_state_wait2() function which does the same
but does not use tst_brkm() to exit on failure. Instead of that it
returns non-zero exit value and prints the cause of the failure into the
stderr.

Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
fcntl/fcntl31.c: add I/O availability signals test for fcntl(2)

create a new case to test F_GETOWN, F_SETOWN, F_GETOWN_EX,
F_SETOWN_EX, F_GETSIG, F_SETSIG for fcntl(2)

Signed-off-by: Xiaoguang Wang <wangxg.fnst@cn.fujitsu.com>