[rfa/testsuite] gdb.threads/tls.{exp,c} fixes

[Michael Elizabeth Chastain]

Committed.

Michael C

2003-07-29  Michael C  <mec@shout.net>

	* gdb.threads/tls.c (spin): Check errno only if sem_wait
	actually failed.
	(do_pass): Likewise.
	* gdb.threads/tls.exp: Always initialize no_of_threads.