kcmp: Move kcmp.h into uapi

kcmp.h appears to be part of the API, it's documented in kcmp(2), and
the selftests/kcmp code uses it. So move it to uapi so it's actually
exported.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
diff --git a/include/uapi/linux/Kbuild b/include/uapi/linux/Kbuild
index b70237e..1cf50d6 100644
--- a/include/uapi/linux/Kbuild
+++ b/include/uapi/linux/Kbuild
@@ -209,6 +209,7 @@
 header-y += ixjuser.h
 header-y += jffs2.h
 header-y += joystick.h
+header-y += kcmp.h
 header-y += kd.h
 header-y += kdev_t.h
 header-y += kernel-page-flags.h