termcap: add entry for Alacritty

Out of the box on other platforms, alacritty reports TERM=alacritty. This requires an updated terminfo/termcap database that contains an entry for alacritty. Prior to this change, when you ssh into a FreeBSD machine using a default configuration of alacritty on a client system, it reports this in motd(5):

No entry for terminal type "alacritty";
using dumb terminal settings.

This change adds a termcap entry for alacritty, converted from the upstream-provided alacritty.info using tic -C.

Signed-off-by: Siva Mahadevan <me@svmhdvn.name>

MFC After: 3 days