soc: qcom: llcc cleanup to get rid of sdm845 specific driver file

A single file should suffice the need to program the llcc for
various platforms. Get rid of sdm845 specific driver file to
make way for a more generic driver.

Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>