[PATCH] uml build fix

This is needed to fix UML compilation given that alternatives_smp_module_add
and alternatives_smp_module_del are null inline functions if !CONFIG_SMP.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

arch/um/kernel/um_arch.c

@@ -495,6 +495,7 @@ void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
 {
 }
 
+#ifdef CONFIG_SMP
 void alternatives_smp_module_add(struct module *mod, char *name,
 				 void *locks, void *locks_end,
 				 void *text,  void *text_end)
@@ -504,3 +505,4 @@ void alternatives_smp_module_add(struct module *mod, char *name,
 void alternatives_smp_module_del(struct module *mod)
 {
 }
+#endif