x86: fix cpu MHz reporting for AMD family 0x11

Fix cpu MHz reporting for AMD family 0x11 when powernow-k8 is
disabled.

Just adhere to the CONSTANT_TSC feature bit for AMD CPUs when deciding
whether cpu_khz needs calibration. The additional check for CPU family
is not needed and prevents calibration for future CPUs.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/time_64.c

@@ -120,8 +120,7 @@ void __init time_init(void)
 
 	cpu_khz = tsc_khz;
 	if (cpu_has(&boot_cpu_data, X86_FEATURE_CONSTANT_TSC) &&
-		boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
-		boot_cpu_data.x86 == 16)
+		(boot_cpu_data.x86_vendor == X86_VENDOR_AMD))
 		cpu_khz = calculate_cpu_khz();
 
 	if (unsynchronized_tsc())