include: replace unifdef-y with header-y

unifdef-y and header-y has same semantic.
So there is no need to have both.

Drop the unifdef-y variant and sort all lines again

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/include/linux/sunrpc/Kbuild b/include/linux/sunrpc/Kbuild
index fb438f1..98df211 100644
--- a/include/linux/sunrpc/Kbuild
+++ b/include/linux/sunrpc/Kbuild
@@ -1 +1 @@
-unifdef-y += debug.h
+header-y += debug.h