pvr: fix clang unused function warning
../src/imagination/vulkan/pds/pvr_pds.c:230:31: warning: unused function 'pvr_pds_encode_doutv' [-Wunused-function] static ALWAYS_INLINE uint32_t pvr_pds_encode_doutv(uint32_t cc, ^
Signed-off-by: Frank Binns <frank.binns@imgtec.com>