bcachefs: Ignore backpointers to stripes in ec_stripe_update_extents()

Prep work for stripe backpointers: this path previously would get very
confused at being asked to process (remove redundant replicas) stripes.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2025-02-07 21:26:27 -05:00
commit 7606fb4d26