Incorrect metadata read index in OMASA LS and SH rendering

Basic info

• Commit SHA: main
• Platform: all

Bug description

OMASA LS and SH rendering still uses the dirac_read_idx for fetching the metadata in rendering. As this read index is after JBM updated only once in a frame, the metadata is also updated only once in a frame. md_idx, which is used for other paths, should be used also of OMASA.