[SPARC64]: Drop %gl to 0 before re-enabling PSTATE_IE in rtrap

If we take a window fault, on SUN4V set %gl to zero before we
turn PSTATE_IE back on in %pstate.  Otherwise if we take an
interrupt we'll end up with corrupt register state.

Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc64/kernel/rtrap.S

@@ -333,14 +333,15 @@ user_rtt_fill_fixup:
 
 		mov	%g6, %l1
 		wrpr	%g0, 0x0, %tl
-		wrpr	%g0, RTRAP_PSTATE, %pstate
 
 661:		nop
 		.section		.sun4v_1insn_patch, "ax"
 		.word			661b
 		SET_GL(0)
 		.previous
 
+		wrpr	%g0, RTRAP_PSTATE, %pstate
+
 		mov	%l1, %g6
 		ldx	[%g6 + TI_TASK], %g4
 		LOAD_PER_CPU_BASE(%g5, %g6, %g1, %g2, %g3)