drivers/generic/max98357a: Add extra error handling

It is possible that acpi_device_scope() and acpi_device_name() can
return NULL to indicate an error, so add error handling to check their
return values.

Change-Id: I4c7ab0c592845d9d5f142e078fc2b505a99ecd12
Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Found-by: Coverity CID 1362592
Reviewed-on: https://review.coreboot.org/c/coreboot/+/33028
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

0 files changed, 0 insertions, 0 deletions