tipc: delete TIPC_ADVANCED Kconfig variable

There used to be a time when TIPC had lots of Kconfig knobs the
end user could alter, but they have all been made automatic or
obsolete, with the exception of CONFIG_TIPC_PORTS.  This
previously existing set of options was all hidden under the
TIPC_ADVANCED setting, which does not exist in any code, but
only in Kconfig scope.

Having this now, just to hide the one remaining "advanced"
option no longer makes sense.  Remove it.  Also get rid of the
ifdeffery in the TIPC code that allowed for TIPC_PORTS to be
possibly undefined.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>