[IA64] ia64_set_psr should use srlz.i

The only in kernel use of ia64_set_psr() needs to follow
it with a srlz.i (since it is changing state for PSR.ic).
So it is pointless to issue srlz.d inside this function.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>