Since we are taking a registers, this should never have been an sldi.
Talking to paulus offline, this is the correct fix.
Was introduced by:
 commit 
19ccb76a1938ab364a412253daec64613acbf3df
 Author: Paul Mackerras <paulus@samba.org>
 Date:   Sat Jul 23 17:42:46 2011 +1000
Talking to paulus, this shouldn't be a literal.
Signed-off-by: Michael Neuling <mikey@neuling.org>
CC: <stable@kernel.org> [v3.2+]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
        lwz     r3,VCORE_NAPPING_THREADS(r5)
        lwz     r4,VCPU_PTID(r9)
        li      r0,1
-       sldi    r0,r0,r4
+       sld     r0,r0,r4
        andc.   r3,r3,r0                /* no sense IPI'ing ourselves */
        beq     43f
        mulli   r4,r4,PACA_SIZE         /* get paca for thread 0 */