coresight: funnel: Move ACPI support from AMBA driver to platform driver

Add support for the dynamic funnel device in the platform driver, which can
then be used on ACPI based platforms. This change would allow runtime power
management for ACPI based systems.

The driver would try to enable the APB clock if available. Also, rename the
code to reflect the fact that it now handles both static and dynamic
funnels. But first this refactors funnel_probe() making sure it can be used
both for platform and AMBA drivers, by moving the pm_runtime_put() to the
callers.

Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: James Clark <james.clark@arm.com>
Cc: linux-acpi@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: coresight@lists.linaro.org
Tested-by: Sudeep Holla <sudeep.holla@arm.com> # Boot and driver probe only
Acked-by: Sudeep Holla <sudeep.holla@arm.com> # For ACPI related changes
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>