alpha: fix reboot on Avanti platform

BugLink: http://bugs.launchpad.net/bugs/1756121

commit 55fc633c upstream.

We need to define NEED_SRM_SAVE_RESTORE on the Avanti, otherwise we get
machine check exception when attempting to reboot the machine.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

arch/alpha/kernel/pci_impl.h

@@ -143,7 +143,8 @@ struct pci_iommu_arena
 };
 
 #if defined(CONFIG_ALPHA_SRM) && \
-    (defined(CONFIG_ALPHA_CIA) || defined(CONFIG_ALPHA_LCA))
+    (defined(CONFIG_ALPHA_CIA) || defined(CONFIG_ALPHA_LCA) || \
+     defined(CONFIG_ALPHA_AVANTI))
 # define NEED_SRM_SAVE_RESTORE
 #else
 # undef NEED_SRM_SAVE_RESTORE