mfd: sm501: Add check for platform_driver_register()

[ Upstream commit 8325a6c24ad78b8c1acc3c42b098ee24105d68e5 ]

As platform_driver_register() can return error numbers,
it should be better to check platform_driver_register()
and deal with the exception.

Fixes: b6d6454f ("[PATCH] mfd: SM501 core driver")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20220913091112.1739138-1-jiasheng@iscas.ac.cn


Signed-off-by: Sasha Levin <sashal@kernel.org>