z_idataoff here is an absolute physical offset, so it should use
erofs_off_t (64 bits at least). Otherwise, it'll get trimmed and
cause the decompresion failure.
Fixes: ab92184ff8f1 ("erofs: add on-disk compressed tail-packing inline support")
Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>