soc: qcom: dcc: Drop driver for now

Arnd asks for the DCC driver to be dropped for now, in order to allow
for more thorough review, by a wider audience, of the ABI introduced.

The Devicetree binding is adequately describing the hardware block, so
this is kept.

Requested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>