Use SET_ERROR for more errors in FreeBSD vnops

We should use SET_ERROR when we first get an error.

Add it in the FreeBSD xattr implementations where missing.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes #12356