v5.15-rc1 + 20210927135559.738-[23456]-srinivas.kandagatla@linaro.org

This immutable branch is based on v5.15-rc1 and contains the following
patches extending the existig APR driver to also implement GPR:
20210927135559.738-2-srinivas.kandagatla@linaro.org
20210927135559.738-3-srinivas.kandagatla@linaro.org
20210927135559.738-4-srinivas.kandagatla@linaro.org
20210927135559.738-5-srinivas.kandagatla@linaro.org
20210927135559.738-6-srinivas.kandagatla@linaro.org