x86, xen, vdso: fix build error

fix:

   arch/x86/xen/built-in.o: In function `xen_enable_syscall':
   (.cpuinit.text+0xdb): undefined reference to `sysctl_vsyscall32'

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 9cce4a92aac..3e11779755c 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -144,7 +144,9 @@ void __cpuinit xen_enable_syscall(void)
                 if (ret != 0) {
                         printk(KERN_INFO "Xen: 32-bit syscall not supported: disabling vdso\n");
                         setup_clear_cpu_cap(X86_FEATURE_SYSCALL32);
+#ifdef CONFIG_COMPAT
                         sysctl_vsyscall32 = 0;
+#endif
                 }
         }
 #endif /* CONFIG_X86_64 */