Update port infrastructure.
Do not build package for this port, because it depends on kernel sources.
Take maintainership.
Requested by: glebius [1]
Approved by: portmgr (krion)
2) Correct filename for patch, now it name is patch-sys-dev-ltmdm-ltmdmsio.c
3) Fix run on recent -CURRENT by removing ttyclose() calls
Symptoms:
# kldload ltmdm.ko
kldload: can't load ltmdm.ko: No such file or directory
# dmesg | head -1
link_elf: symbol ttyclose underfined
4) Move PORTDOCS from pkg-plist to Makefile
5) Utilize DATADIR macro
5) Reorganize install target for PORTDOCS
6) Bump ${PORTREVISION}
