mailbox: remove unnecessary platform_set_drvdata()
mailbox: remove unnecessary platform_set_drvdata()

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.

Signed-off-by: Jingoo Han <fc379137a64feb86ce38ec5811a14280acc1ccfc@samsung.com>
Acked-by: Suman Anna <68636d6b0a4dfe1213ee9d7712e75a8cc339119f@ti.com>
Signed-off-by: Tony Lindgren <1001e8702733cced254345e193c88aaa47a4f5de@atomide.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs