drm/i915/ehl: All EHL ports are combo phys

Unlike ICL, all of the output ports are combo phys so just return
true in intel_port_is_combophy for all EHL ports to indicate that.

v2: Return false in intel_port_is_tc since no EHL ports are TC. (Jose)

Cc: Jose Souza <jose.souza@intel.com>
Signed-off-by: Bob Paauwe <bob.j.paauwe@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190320211547.519266-1-bob.j.paauwe@intel.com