TIFF 6 spec: "Do not use both strip-oriented and tile-oriented fields in the same TIFF file."

Fixes: null pointer use, crash
Fixes: crash-762680f9d1b27f9b9085e12887ad44893fb2b020
Found-by: Shiziru <lunasl@protonmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>