Add Linux:ZFS compatibility

The ZFS port on Linux behaves just like ext3 for certain tests.
This really has the most to do with Linux VFS and not the ZFS
backend implementation.  Since we expect ext3-like behavior
due to the VFS add a Linux:ZFS case to ensure these are not
marked as failures.

tests/chown/00.t

@@ -156,7 +156,7 @@ expect 0 chmod ${n0} 06555
 expect 06555 lstat ${n0} mode
 expect 0 -u 65534 -g 65533,65532 chown ${n0} 65534 65532
 case "${os}:${fs}" in
-Linux:ext3|Linux:ntfs-3g)
+Linux:ext3|Linux:ntfs-3g|Linux:ZFS)
 	expect 06555,65534,65532 lstat ${n0} mode,uid,gid
         ;;
 *)
@@ -167,7 +167,7 @@ expect 0 chmod ${n0} 06555
 expect 06555 lstat ${n0} mode
 expect 0 -u 65534 -g 65533,65532 -- chown ${n0} -1 65533
 case "${os}:${fs}" in
-Linux:ext3|Linux:ntfs-3g)
+Linux:ext3|Linux:ntfs-3g|Linux:ZFS)
 	expect 06555,65534,65533 lstat ${n0} mode,uid,gid
         ;;
 *)
@@ -283,7 +283,7 @@ sleep 1
 expect 0 -- chown ${n0} -1 -1
 ctime2=`${fstest} stat ${n0} ctime`
 case "${os}:${fs}" in
-Linux:ext3)
+Linux:ext3|Linux:ZFS)
 	test_check $ctime1 -lt $ctime2
         ;;
 *)
@@ -298,7 +298,7 @@ sleep 1
 expect 0 -- chown ${n0} -1 -1
 ctime2=`${fstest} stat ${n0} ctime`
 case "${os}:${fs}" in
-Linux:ext3)
+Linux:ext3|Linux:ZFS)
 	test_check $ctime1 -lt $ctime2
         ;;
 *)
@@ -313,7 +313,7 @@ sleep 1
 expect 0 -- chown ${n0} -1 -1
 ctime2=`${fstest} stat ${n0} ctime`
 case "${os}:${fs}" in
-Linux:ext3)
+Linux:ext3|Linux:ZFS)
 	test_check $ctime1 -lt $ctime2
         ;;
 *)
@@ -328,7 +328,7 @@ sleep 1
 expect 0 -- lchown ${n0} -1 -1
 ctime2=`${fstest} lstat ${n0} ctime`
 case "${os}:${fs}" in
-Linux:ext3)
+Linux:ext3|Linux:ZFS)
 	test_check $ctime1 -lt $ctime2
         ;;
 *)