mfd: arizona: Add missing statics to the of_match_tables

When the match tables were split for I2C and SPI a static should have
been added since the tables are no longer exported.

Fixes: 3f65555c ("mfd: arizona: Split of_match table into I2C and SPI versions")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220104165435.26782-1-ckeepax@opensource.cirrus.com