Support disabling individual cpufreq drivers with hints, e.g.,

hint.ichss.0.disabled="1"

sys/dev/acpica/acpi_perf.c

@@ -165,6 +165,9 @@ acpi_perf_probe(device_t dev)
 	ACPI_BUFFER buf;
 	int error, rid, type;
 
+	if (resource_disabled("acpi_perf", 0))
+		return (ENXIO);
+
 	/*
 	 * Check the performance state registers.  If they are of type
 	 * "functional fixed hardware", we attach quietly since we will

sys/dev/acpica/acpi_throttle.c

@@ -166,6 +166,9 @@ static int
 acpi_throttle_probe(device_t dev)
 {
 
+	if (resource_disabled("acpi_throttle", 0))
+		return (ENXIO);
+
 	device_set_desc(dev, "ACPI CPU Throttling");
 	return (0);
 }

sys/dev/cpufreq/ichss.c

@@ -214,6 +214,9 @@ ichss_probe(device_t dev)
 	device_t est_dev, perf_dev;
 	int error, type;
 
+	if (resource_disabled("ichss", 0))
+		return (ENXIO);
+
 	/*
 	 * If the ACPI perf driver has attached and is not just offering
 	 * info, let it manage things.  Also, if Enhanced SpeedStep is

sys/i386/cpufreq/est.c

@@ -593,6 +593,9 @@ est_probe(device_t dev)
 	device_t perf_dev;
 	uint64_t msr;
 	int error, type;
+        
+	if (resource_disabled("est", 0))
+		return (ENXIO);
 
 	/*
 	 * If the ACPI perf driver has attached and is not just offering