gpio: sama5d2-piobu: drop of_match_ptr for ID table
The driver can match only via the DT table so the table should be always
used and the of_match_ptr does not have any sense (this also allows ACPI
matching via PRP0001, even though it might not be relevant here).
drivers/gpio/gpio-sama5d2-piobu.c:230:34: error: ‘sama5d2_piobu_ids’ defined but not used [-Werror=unused-const-variable=]