HRTF ROM tables should be defined as 'const'

HRTF ROM tables should be defined as 'const'. This is missing for some ROM tables in the recent HRTF update, e.g. Crend ROM tables:

uint16_t CRendBin_Combined_HRIR_pIndex_frequency_max_32kHz[HRTF_LS_CHANNELS][BINAURAL_CHANNELS][1];
uint16_t *CRendBin_Combined_HRIR_pIndex_frequency_max_diffuse_32kHz[BINAURAL_CHANNELS];
int16_t *CRendBin_Combined_HRIR_coeff_diffuse_re_32kHz_fx[BINAURAL_CHANNELS];
int16_t *CRendBin_Combined_HRIR_coeff_diffuse_im_32kHz_fx[BINAURAL_CHANNELS];

Note that some instances are corrected in !1698 (merged) while others need more work.