Incorrect parsing of nnpfc_constant_patch_size_flag

[hallapur]

The flag is parsed incorrectly which causes decoder crash.

if (sei.m_constantPatchSizeFlag)
{
sei_read_flag(pDecodedMessageOutputStream, val, "nnpfc_constant_patch_size_flag");
sei.m_constantPatchSizeFlag = val;
}
else

Correct way to parse is as follows:

sei_read_flag(pDecodedMessageOutputStream, val, "nnpfc_constant_patch_size_flag");
sei.m_constantPatchSizeFlag = val;
if (sei.m_constantPatchSizeFlag)
{

sei_read_uvlc(pDecodedMessageOutputStream, val, "nnpfc_patch_width_minus1");
sei.m_patchWidthMinus1 = val;

sei_read_uvlc(pDecodedMessageOutputStream, val, "nnpfc_patch_height_minus1");
sei.m_patchHeightMinus1 = val;

}
else

[hallapur]

Also, nnpfc_overlap is parsed twice, before and after nnpfc_constant_patch_size_flag parsing.

[hallapur]

Proposed fix in this merge request:
​https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM/-/merge_requests/2586

[XiangLi]

The suggested fix has been merged.