CVE-2022-49650

In the Linux kernel, the following vulnerability has been resolved:

dmaengine: qcom: bam_dma: fix runtime PM underflow

Commit dbad41e7bb5f ("dmaengine: qcom: bam_dma: check if the runtime pm enabled")
caused unbalanced pm_runtime_get/put() calls when the bam is
controlled remotely. This commit reverts it and just enables pm_runtime
in all cases, the clk_* functions already just nop when the clock is NULL.

Also clean up a bit by removing unnecessary bamclk null checks.