zfs-module: disable separate build directory

ZFS can't compile in a separate build directory on newer kernels, which
I hit when building Linux 6.12.

The problem is described in [1] and fixed in [2] but that fix is already
present in 2.3.4 and the problem still persists in Yocto builds.

I don't know what's wrong, it seems to be an issue deep in the guts of
Kbuild, but building in-tree (${S} == ${B}) seems to work so just do
that.

[1] openzfs/zfs#17321
[2] openzfs/zfs#17517

Author: aswild

recipes-filesystems/openzfs/zfs-module_git.bb

@@ -2,7 +2,7 @@ require openzfs.inc
 
 SUMMARY = "OpenZFS for Linux"
 
-inherit autotools module python3native pkgconfig
+inherit autotools-brokensep module python3native pkgconfig
 
 # OpenZFS builds kernel modules using autoconf. It's both clever and cursed.
 EXTRA_OECONF = " \