ppc: fix result of DLMZB when no zero bytes are found

It must return 8 and place 8 in XER, but the current code uses
i directly which is 9 at this point of the code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Tom Musta <tommusta@gmail.com>
Signed-off-by: Alexander Graf <agraf@suse.de>

target-ppc/int_helper.c

diff --git a/target-ppc/int_helper.c b/target-ppc/int_helper.c
index 29ff4f6..83c1ad0 100644
--- a/target-ppc/int_helper.c
+++ b/target-ppc/int_helper.c
@@ -2556,6 +2556,7 @@
         }
         i++;
     }
+    i = 8;
     if (update_Rc) {
         env->crf[0] = 0x2;
     }