spi-nor: s25fl512s supports region locking

Both the BP[0-2] bits and the TBPROT bit are supported on this chip.
Tested and verified on a Cypress s25fl512s.

Signed-off-by: Jonas Bonn <jonas@norrbonn.se>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>