The kernel test robot reports missing functions. Add them.

hppa-linux-ld: drivers/firmware/arm_scmi/perf.o: in function `scmi_perf_fc_ring_db':
 (.text+0x610): undefined reference to `ioread64_hi_lo'
 (.text+0x63c): undefined reference to `iowrite64_hi_lo'
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Helge Deller <deller@gmx.de>