ZFS: fix the zpool_get_002_pos test

ZFS has grown some additional properties that hadn't been added to the
config file yet.  While I'm here, improve the error message, and remove a
superfluous command.

MFC after:	2 weeks
Sponsored by:	Axcient

tests/sys/cddl/zfs/tests/cli_root/zpool_get/zpool_get.cfg

@@ -54,6 +54,7 @@ typeset -a properties=(
     "fragmentation"
     "leaked"
     "bootsize"
+    "checkpoint"
     "feature@async_destroy"
     "feature@empty_bpobj"
     "feature@lz4_compress"
@@ -66,11 +67,14 @@ typeset -a properties=(
     "feature@bookmarks"
     "feature@filesystem_limits"
     "feature@large_blocks"
+    "feature@large_dnode"
     "feature@sha512"
     "feature@skein"
     # "feature@edonr" Edonr is not yet implemented on FreeBSD
     "feature@device_removal"
     "feature@obsolete_counts"
+    "feature@zpool_checkpoint"
+    "feature@spacemap_v2"
 )
 
 export DISK=${DISKS%% *}

tests/sys/cddl/zfs/tests/cli_root/zpool_get/zpool_get_002_pos.ksh

@@ -96,10 +96,10 @@ done
 # increment the counter to include the header line
 i=$(( $i + 1 ))
 
-COUNT=$($WC $TMPDIR/values.${TESTCASE_ID} | $AWK '{print $1}')
+COUNT=$($WC $TMPDIR/values.${TESTCASE_ID})
 if [ $i -ne $COUNT ]
 then
-	log_fail "Length of output $COUNT was not equal to number of props + 1."
+	log_fail "Length of output $COUNT was not equal to number of props + 1 ($i)."
 fi