Fix wrong key indexes in package verification logs.

If the verification fails with the key, 'continue' will be performed and
the increment of the index at the end of the loop will be skipped.
This CL fixes it.

Test: check the log and see correct key indexes.
Change-Id: I3d1b2b8b4189f5fedbf8828f5e8e0d0b2e277c6a