update ZFS to 2.1.3

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

diff --git a/submodules/zfsonlinux b/submodules/zfsonlinux
index 531eac33046f7e207226b428e399bcab173b7b6b..9a75bb8d65720c9b9eddaff78767b3e09b4b06d9 160000 (submodule)
--- a/submodules/zfsonlinux
+++ b/submodules/zfsonlinux
@@ -1 +1 @@
-Subproject commit 531eac33046f7e207226b428e399bcab173b7b6b
+Subproject commit 9a75bb8d65720c9b9eddaff78767b3e09b4b06d9