[IA64] Optimize ticket spinlocks in fsys_rt_sigprocmask
Tony's fix (f574c843191728d9407b766a027f779dcd27b272) has a small bug,
it incorrectly uses "r3" as a scratch register in the first of the two
unlock paths ... it is also inefficient. Optimize the fast path again.
Signed-off-by: Petr Tesarik <firstname.lastname@example.org>
Signed-off-by: Tony Luck <email@example.com>