Documentation: KVM: fix warning in "make htmldocs"

commit efbc6bd0 upstream.

The warning

 Documentation/virt/kvm/locking.rst:31: ERROR: Unexpected indentation.

is caused by incorrectly treating a line as the continuation of a paragraph,
rather than as the first line in a bullet list.

Fixed: 44d17459 ("KVM: Use dedicated mutex to protect kvm_usage_count to avoid deadlock")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>