cpufreq: Remove support for hardware P-state chips from powernow-k8

These chips are now supported by acpi-cpufreq, so we can delete all the
code handling them.

Andre: Tighten the deprecation warning message. Trigger load of
acpi-cpufreq and let the load of the module finally fail.
This avoids the problem of users ending up without any cpufreq support
after the transition.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

drivers/cpufreq/Makefile

@@ -19,7 +19,7 @@ obj-$(CONFIG_CPU_FREQ_TABLE)		+= freq_table.o
 # K8 systems. ACPI is preferred to all other hardware-specific drivers.
 # speedstep-* is preferred over p4-clockmod.
 
-obj-$(CONFIG_X86_POWERNOW_K8)		+= powernow-k8.o mperf.o
+obj-$(CONFIG_X86_POWERNOW_K8)		+= powernow-k8.o
 obj-$(CONFIG_X86_ACPI_CPUFREQ)		+= acpi-cpufreq.o mperf.o
 obj-$(CONFIG_X86_PCC_CPUFREQ)		+= pcc-cpufreq.o
 obj-$(CONFIG_X86_POWERNOW_K6)		+= powernow-k6.o