DngOpcodes::DeltaRowOrCol: sanitize count of 'delta' elements.
DngOpcodes::DeltaRowOrCol: sanitize count of 'delta' elements.

While the logic seems sound, apparently no RPU sample uses
any of these opcodes, so.

Also, this might be incorrect in some edge-cases, e.g. with
some strange pitch.

darktable-org/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed,darktable-org/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed