btrfs: refactor allocation size calculation in alloc_btrfs_io_context()

Use struct_size() to replace the open-coded calculation, remove the
comment as use of the helper is self explanatory.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Mehdi Ben Hadj Khelifa <mehdi.benhadjkhelifa@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Mehdi Ben Hadj Khelifa 2025-09-30 11:03:44 +01:00 • committed by David Sterba
commit 2346b966c6