remoteproc/keystone: Fix circular dependencies for ARM configs

Drop the dependency on RESET_CONTROLLER for the Keystone remoteproc
driver to resolve some circular dependencies around different choices
for RESET_CONTROLLER on common ARM configs. This dependency is
inherent as the RESET_CONTROLLER will be enabled due to the enabled
ARCH_HAS_RESET_CONTROLLER for ARCH_KEYSTONE.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>