mtd: spi-nor: Add spi flash lock config option

mtd: spi-nor: Add spi flash lock config option

Provide an explicit configuration option to disable default "lock"
of any flash chip which supports locking. By disabling the lock
config will save some amount of memory and also don't expose the
lock functionality to the users i.e., via sf protect command.

Signed-off-by: Venkatesh Yadav Abbarapu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Michal Simek <[email protected]>