sysutils/dsbmd: Update to 1.4

Changes since 1.3

• Detach md(4) devices when they are ejected.
• Open listening socket before scanning attached devices, so that clients can connect even if DSBMD is busy with slow devices.
• Ignore the deprecated "large" mount option for msdosfs on FreeBSD >= 12. This is necessary for users upgrading their system to FreeBSD 12 without adjusting dsbmd.conf. Thanks to Samy Mahmoudi for pointing this out. [1]
• Support for bootable USB drives with ISO-9660 has been added. Thanks to jmp-2
• Support for nvd(4) and uzip memory disks has been added.

PR: 230256 [1]
PR: 230559
Submitted by: Marcel Kaiser <mk@nic-nac-project.org> (maintainer)
Reported by: Samy Mahmoudi <samy.mahmoudi@gmail.com> [1]