Driver core: exclude kobject_uevent.c for !CONFIG_HOTPLUG

Move uevent specific logic from the core into kobject_uevent.c, which
does no longer require to link the unused string array if hotplug
is not compiled in.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/lib/Makefile b/lib/Makefile
index 4f3f3e2..6c4ea33 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -10,7 +10,7 @@
 lib-$(CONFIG_MMU) += ioremap.o
 lib-$(CONFIG_SMP) += cpumask.o
 
-lib-y	+= kobject.o kref.o kobject_uevent.o klist.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
@@ -20,6 +20,7 @@
 CFLAGS_kobject_uevent.o += -DDEBUG
 endif
 
+lib-$(CONFIG_HOTPLUG) += kobject_uevent.o
 obj-$(CONFIG_GENERIC_IOMAP) += iomap.o
 obj-$(CONFIG_HAS_IOMEM) += iomap_copy.o devres.o
 obj-$(CONFIG_CHECK_SIGNATURE) += check_signature.o