cpufreq: add cpufreq_get() stub for CONFIG_CPU_FREQ=n

When CONFIG_CPU_FREQ is disabled, cpufreq_get() needs a stub.  Used by kvm
(although it looks like a bit of the kvm code could be omitted when
CONFIG_CPU_FREQ is disabled).

arch/x86/built-in.o: In function `kvm_arch_init':
(.text+0x10de7): undefined reference to `cpufreq_get'

(Needed in linux-next's KVM tree, but it's correct in 2.6.32).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Tested-by: Eric Paris <eparis@redhat.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/cpufreq.h

@@ -291,8 +291,15 @@ struct global_attr {
 int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu);
 int cpufreq_update_policy(unsigned int cpu);
 
+#ifdef CONFIG_CPU_FREQ
 /* query the current CPU frequency (in kHz). If zero, cpufreq couldn't detect it */
 unsigned int cpufreq_get(unsigned int cpu);
+#else
+static inline unsigned int cpufreq_get(unsigned int cpu)
+{
+	return 0;
+}
+#endif
 
 /* query the last known CPU freq (in kHz). If zero, cpufreq couldn't detect it */
 #ifdef CONFIG_CPU_FREQ