norflash: Wait for WSM bit in lock/unlock

lock/unlock operation must wait until WSM bit
is set. Since we do not allow to loop forever then these functions
must return an error if WSM bit isn't enabled after a number of tries.

Change-Id: I21c9e292b514b28786ff4a225128bcd8c1bfa999
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>
2 files changed