lib: move bitmap.o from lib-y to obj-y.

mac80211 has a reference to __bitmap_empty() via bitmap_empty().  In
lib/bitmap.c this is flagged with an EXPORT_SYMBOL(), but this is
ultimately ineffective due to bitmap.o being linked in lib-y, resulting in:

ERROR: "__bitmap_empty" [net/mac80211/mac80211.ko] undefined!

Moving bitmap.o to obj-y fixes this up.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Cc: "John W. Linville" <linville@tuxdriver.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

lib/Makefile

@@ -4,7 +4,7 @@
 
 lib-y := ctype.o string.o vsprintf.o cmdline.o \
 	 rbtree.o radix-tree.o dump_stack.o \
-	 idr.o int_sqrt.o bitmap.o extable.o prio_tree.o \
+	 idr.o int_sqrt.o extable.o prio_tree.o \
 	 sha1.o irq_regs.o reciprocal_div.o argv_split.o \
 	 proportions.o prio_heap.o
 
@@ -14,7 +14,7 @@ lib-$(CONFIG_SMP) += cpumask.o
 lib-y	+= kobject.o kref.o klist.o
 
 obj-y += div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
-	 bust_spinlocks.o hexdump.o kasprintf.o
+	 bust_spinlocks.o hexdump.o kasprintf.o bitmap.o
 
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG