btrfs: zoned: initialize device's zone info for seeding
In the Linux kernel, the following vulnerability has been resolved:

btrfs: zoned: initialize device's zone info for seeding

When performing seeding on a zoned filesystem it is necessary to
initialize each zoned device's btrfs_zoned_device_info structure,
otherwise mounting the filesystem will cause a NULL pointer dereference.

This was uncovered by fstests' testcase btrfs/163.