dt-bindings: fsi: Add optional property no-scan-on-init

Add an optional FSI master property 'no-scan-on-init.  This
can be specified to indicate that a master should not be
automatically scanned at init time.  This is required in cases
where a scan could interfere with another FSI master on the same
bus.

Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>