CDVD | CHD: Account for pre/post gap offsets when filling TOC

This will fix discs with tracks with both an INDEX 00 and INDEX 01

pcsx2/CDVD/ChdFileReader.cpp

@@ -281,7 +281,7 @@ bool ChdFileReader::ParseTOC(u64* out_frame_count, std::vector<toc_entry>& entri
 {
 	u64 total_frames = 0;
 	int max_found_track = -1;
-
+	u64 total_gap_frames = 0;
 	for (int search_index = 0;; search_index++)
 	{
 		char metadata_str[256];