x86/tsc: Do feature check as the very first thing

Do the feature check as the very first thing in the function. Everything
else comes after that and is meaningless work if the TSC CPUID bit is
not even set. Switch to cpu_feature_enabled() too, while at it.

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/Y5990CUCuWd5jfBH@zn.tnic

Author: bp3tk0v

arch/x86/kernel/tsc.c

@@ -1509,18 +1509,18 @@ void __init tsc_early_init(void)
 
 void __init tsc_init(void)
 {
+	if (!cpu_feature_enabled(X86_FEATURE_TSC)) {
+		setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
+		return;
+	}
+
 	/*
 	 * native_calibrate_cpu_early can only calibrate using methods that are
 	 * available early in boot.
 	 */
 	if (x86_platform.calibrate_cpu == native_calibrate_cpu_early)
 		x86_platform.calibrate_cpu = native_calibrate_cpu;
 
-	if (!boot_cpu_has(X86_FEATURE_TSC)) {
-		setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
-		return;
-	}
-
 	if (!tsc_khz) {
 		/* We failed to determine frequencies earlier, try again */
 		if (!determine_cpu_tsc_frequencies(false)) {