Multiple bugs in preceding IRAP, GDR pictures and subpictures

[Vadim]

1. In m_prevGDRInSameLayerPOC{ MAX_INT }, m_pocCRA{ MAX_INT } only the first element is initialized to the specified value, others are 0. It means it is not correct for the second layer and onward. MAX_INT is not the correct value for IRAP either.

2. Initializing preceding IRAP POC to MAX_INT or 0 is incorrect for the very first IRAP picture as some reference POCs if present can be negative and constraint check fails, it should be initialized with a large negative number, i.e. m_pocCRA{ -MAX_INT }, which actually should be std::fill_n(m_pocCRA[i], MAX_VPS_LAYERS, -MAX_INT);

3. Same problem is for preceding IRAP subpicture, it should be m_prevIRAPSubpicPOC( -MAX_INT ), std::fill_n( m_prevIRAPSubpicPOC[i], MAX_NUM_SUB_PICS, -MAX_INT ).

4. Very likely, it is the same problem for preceding GDR pictures and sub-pictures, it should be checked.

[ZhipinDeng]

Thanks for your suggestions! I submitted the following MR for it. I would appreciate if you could have a review.

​https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM/-/merge_requests/1873