nvmem_cell_read() API fills in the argument 'len' with
the number of bytes read from the cell. Many users don't
care about this length value. So allow users to pass a
NULL pointer to this len field.
Signed-off-by: NVivek Gautam <vivek.gautam@codeaurora.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>