git_connect(): use common return point

git_connect(): use common return point

Use only one return point from git_connect(), doing the

    free();
    return conn;

only at one place in the code.

There may be a little confusion what the variable "host" is for.  At
some places it is only the host part, at other places it may include
the port number, so change host into hostandport here.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>