KVM: PPC: e500: fix couple of shift operations on 64 bits

Fix couple of cases where we shift left a 32-bit
value thus might get truncated results on 64-bit
targets.

Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Suggested-by: Scott Wood <scotttwood@freescale.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>