net: netcp: remove unused kconfig option and code

Currently CPTS is built into the netcp driver even though there is no
call out to the CPTS driver. This patch removes the dependency in Kconfig
and remove cpts.o from the Makefile for NetCP.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>