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