Add data for 2420. Big thanks to Paul Walmsley <paul@pwsan.com>
for generating usable mux data out of TRMs.

Cc: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>