checkpatch: remove rule on non-indented labels

There are 508 non-indented (non-default) labels, and 511 that are
indented.  So the rule is debatable at least.  Actually, in the
common case of labels at the outermost scope, there is really just
one place where to put the label, so the rule is just wrong IMHO.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
