dma: ste_dma40: Don't require CONFIG_PM_RUNTIME

While probing, don't rely on CONFIG_PM_RUNTIME to be configured.
Instead, let's power up the device and make it fully operational.
Update the runtime PM status to reflect the active state.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>