mtd: cfi_probe: add support for SST 0x0701 vendorname

SST 39VF160x and 39VF320x chips use vendorname id 0x0701 and alternative
unlock addresses. Add support for them in cfi_probe.c.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>