lib: enable building KUnit in lib/

KUnit is a new unit testing framework for the kernel and when used is
built into the kernel as a part of it. Add KUnit to the lib Kconfig and
Makefile to allow it to be actually built.
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Kees Cook <keescook@chromium.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

lib/Kconfig.debug

@@ -1664,6 +1664,8 @@ config PROVIDE_OHCI1394_DMA_INIT
 
 	  See Documentation/debugging-via-ohci1394.txt for more information.
 
+source "lib/kunit/Kconfig"
+
 menuconfig RUNTIME_TESTING_MENU
 	bool "Runtime Testing"
 	def_bool y

lib/Makefile

@@ -92,6 +92,8 @@ obj-$(CONFIG_TEST_MEMINIT) += test_meminit.o
 
 obj-$(CONFIG_TEST_LIVEPATCH) += livepatch/
 
+obj-$(CONFIG_KUNIT) += kunit/
+
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG
 CFLAGS_kobject_uevent.o += -DDEBUG