x86, hyperv: Move a variable to avoid an unused variable warning

The variable hv_lapic_frequency causes an unused variable warning if
CONFIG_X86_LOCAL_APIC is disabled.  Since the variable is only used
inside a small if statement, move the declaration of that variable
into the if statement itself.

Cc: K. Y. Srinivasan <kys@microsoft.com>
Link: http://lkml.kernel.org/r/1381444224-3303-1-git-send-email-kys@microsoft.comSigned-off-by: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/kernel/cpu/mshyperv.c

@@ -70,8 +70,6 @@ static struct clocksource hyperv_cs = {
 
 static void __init ms_hyperv_init_platform(void)
 {
-	u64	hv_lapic_frequency;
-
 	/*
 	 * Extract the features and hints
 	 */
@@ -86,6 +84,8 @@ static void __init ms_hyperv_init_platform(void)
 		/*
 		 * Get the APIC frequency.
 		 */
+		u64	hv_lapic_frequency;
+
 		rdmsrl(HV_X64_MSR_APIC_FREQUENCY, hv_lapic_frequency);
 		hv_lapic_frequency = div_u64(hv_lapic_frequency, HZ);
 		lapic_timer_frequency = hv_lapic_frequency;