arm64: dts: qcom: qrb5165-rb5: add slpi remoteproc entry

Add remoteproc nodes definin sensor core on qrb5165-rb5.
Provide proper firmware image names.

For now the slpi device is disabled, it generates tons of 'firmware
crashed' messages in log.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>