mei: gsc: remove unnecessary NULL pointer checks

The .remove() and power management callbacks are never called unless
.probe() has already returned success, which means it has set drvdata to a
non-NULL pointer, so "dev" can never be NULL in the other callbacks.

Remove the unnecessary checks.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20240229181300.352077-2-helgaas@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>