ZTS: Various test case fixes

* devices_001_pos and devices_002_neg - Failing after FreeBSD ZTS
  merged due to missing 'function' keyword for create_dev_file_linux.

* pool_state - Occasionally fails due to an insufficient delay
  before checking 'zpool status'.  Increasing the delay from 1 to 3
  seconds resolved the issue in local testing.

* procfs_list_basic - Fails when run in-tree because the logged
  command is actually 'lt-zfs'.  Updated the regex accordingly.

Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Kjeld Schouten <kjeld@schouten-lebbing.nl>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9748

tests/zfs-tests/tests/functional/devices/devices_common.kshlib

@@ -202,7 +202,7 @@ function create_dev_file_illumos
 	return 0
 }
 
-create_dev_file_linux
+function create_dev_file_linux
 {
 	typeset filetype=$1
 	typeset filename=$2

tests/zfs-tests/tests/functional/procfs/pool_state.ksh

@@ -137,7 +137,7 @@ remove_disk $SDISK
 # background since the command will hang when the pool gets suspended.  The
 # command will resume and exit after we restore the missing disk later on.
 zpool scrub $TESTPOOL2 &
-sleep 1		# Give the scrub some time to run before we check if it fails
+sleep 3		# Give the scrub some time to run before we check if it fails
 
 log_must check_all $TESTPOOL2 "SUSPENDED"
 

tests/zfs-tests/tests/functional/procfs/procfs_list_basic.ksh

@@ -48,7 +48,7 @@ function cleanup
 function count_snap_cmds
 {
 	typeset expected_count=$1
-	count=$(grep "command: zfs snapshot $FS@testsnapshot" | wc -l)
+	count=$(grep -E "command: (lt-)?zfs snapshot $FS@testsnapshot" | wc -l)
 	log_must eval "[[ $count -eq $expected_count ]]"
 }