cpufreq: Add Hygon Dhyana support

The Hygon Dhyana CPU supports ACPI P-States, and there is SMBus device
(PCI device ID 0x790b) on the Hygon platform. Add Hygon Dhyana support
to the cpufreq driver by using the code path of AMD family 17h.

Signed-off-by: Pu Wen <puwen@hygon.cn>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: rjw@rjwysocki.net
Cc: viresh.kumar@linaro.org
Cc: bp@alien8.de
Cc: tglx@linutronix.de
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Cc: x86@kernel.org
Cc: thomas.lendacky@amd.com
Cc: rafael@kernel.org
Cc: linux-pm@vger.kernel.org
Link: https://lkml.kernel.org/r/4db6f0f8537a93c172430c446a0297a6ab1c3c2d.1537533369.git.puwen@hygon.cn