It is good practice to define device tree files based on specific
SoCs. Thus, let's not start to create files that are used across
different architectures.
Duplicate the DTSI file for D-Link DAP-2xxx in order to have one
for qca953x and one for qca955x, respectively.
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>