Update ZTS to work on FreeBSD

Update the common ZTS scripts and individual test cases as needed 
in order to allow them to be run on FreeBSD.  The high level goal
is to provide compatibility wrappers whenever possible to minimize
changes to individual test cases.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes #9692

tests/zfs-tests/include/default.cfg.in

@@ -143,7 +143,7 @@ export SPA_MINDEVSIZE=$((64 * 1024 * 1024))
 # For iscsi target support
 export ISCSITGTFILE=/tmp/iscsitgt_file
 export ISCSITGT_FMRI=svc:/system/iscsitgt:default
-if ! is_linux; then
+if ! is_linux && ! is_freebsd; then
 export AUTO_SNAP=$(svcs -a | grep auto-snapshot | grep online | awk \
     '{print $3}')
 fi
@@ -184,6 +184,20 @@ if is_linux; then
 
 
 	NEWFS_DEFAULT_FS="ext2"
+elif is_freebsd; then
+	unpack_opts="xv"
+	pack_opts="cf"
+	verbose="v"
+	unpack_preserve="xpf"
+	pack_preserve="cpf"
+
+	ZVOL_DEVDIR="/dev/zvol"
+	ZVOL_RDEVDIR="/dev/zvol"
+	DEV_DSKDIR="/dev"
+	DEV_RDSKDIR="/dev"
+	DEV_MPATHDIR="/dev/multipath"
+
+	NEWFS_DEFAULT_FS="ufs"
 else
 	unpack_opts="xv"
 	pack_opts="cf"