x86: KVM guest: merge CONFIG_KVM_CLOCK into CONFIG_KVM_GUEST

The distinction between CONFIG_KVM_CLOCK and CONFIG_KVM_GUEST is
not so clear anymore, as demonstrated by recent bugs caused by poor
handling of on/off combinations of these options.

Merge CONFIG_KVM_CLOCK into CONFIG_KVM_GUEST.

Reported-By: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index f4b9b80..b3386ae 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -957,7 +957,7 @@
 	initmem_init();
 	memblock_find_dma_reserve();
 
-#ifdef CONFIG_KVM_CLOCK
+#ifdef CONFIG_KVM_GUEST
 	kvmclock_init();
 #endif