fix typo and simplify spec related to subpicture

[LIJINGYA]

1. Following hightlighted in bold (CtbSizeY ) can be removed
2. Following hightlighted in bold and italic (j) is typo

The list CtbToSubPicIdx[ ctbAddrRs ] for ctbAddrRs ranging from 0 to PicSizeInCtbsY ? 1, inclusive, specifying the conversion from a CTB address in picture raster scan to a subpicture index, is derived as follows:
for( ctbAddrRs = 0; ctbAddrRs < PicSizeInCtbsY; ctbAddrRs++ ) {

posX = ctbAddrRs % PicWidthInCtbsY * CtbSizeY
posY = ctbAddrRs / PicWidthInCtbsY * CtbSizeY
CtbToSubPicIdx[ ctbAddrRs ] = −1
for( i = 0; CtbToSubPicIdx[ ctbAddrRs ] < 0 && i <= sps_num_subpics_minus1; i++ ) { (31)

if( ( posX >= subpic_ctu_top_left_x[ i ] * CtbSizeY ) &&

( posX < ( subpic_ctu_top_left_x[ i ] + subpic_width_minus1[ i ] + 1 ) * CtbSizeY ) &&
( posY >= subpic_ctu_top_left_y[ i ] * CtbSizeY ) &&
( posY < ( subpic_ctu_top_left_y[ i ] + subpic_height_minus1[ i ] + 1 ) * CtbSizeY ) )

CtbToSubPicIdx[ ctbAddrRs ] = i

}

}
The list NumSlicesInSubpic[ i ] and SliceSubpicToPicIdx[ i ][ k ], specifying the number of rectangular slices in the i-th subpicture and picture-level slice index of the k-th slice in the i-th subpicture, are derived is derived as follows:
for( j = 0; j <= sps_num_subpics_minus1; j++ )

NumSlicesInSubpic[ j ] = 0

for( i = 0; i <= num_slices_in_pic_minus1; i++ ) {

posX = CtbAddrInSlice[ i ][ 0 ] % PicWidthInCtbsY * CtbSizeY
posY = CtbAddrInSlice[ i ][ 0 ] / PicWidthInCtbsY * CtbSizeY
for( j = 0; j <= sps_num_subpics_minus1; j++ ) {

if( ( posX >= subpic_ctu_top_left_x[ j ] * CtbSizeY ) && (32)

( posX < ( subpic_ctu_top_left_x[ j ] + subpic_width_minus1[ j ] + 1 ) * CtbSizeY ) &&
( posY >= subpic_ctu_top_left_y[ j ] * CtbSizeY ) &&
( posY < ( subpic_ctu_top_left_y[ j ] + subpic_height_minus1[ j ] + 1 ) * CtbSizeY ) ) {

SliceSubpicToPicIdx[ j ][ NumSlicesInSubpic[ j ] ] = i
NumSlicesInSubpic[ j ]++

}

}

}

[yk]

Good catches, for both aspects. Fixed in v2 of JVET-Q0041, the editorial input, that is being prepared.