UBUNTU: [Packaging] move linux-libc-dev.stub to debian/control.d/

linux-libc-dev is provided only by the master kernel, so there is
no conflict even if we have it under debian/.

Signed-off-by: Masahiro Yamada <masahiro.yamada@canonical.com>
Acked-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com>
Signed-off-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com>

debian/rules

@@ -173,7 +173,7 @@ include $(DROOT)/rules.d/4-checks.mk
 
 control_files := $(DEBIAN)/control.stub.in
 ifeq ($(DEBIAN),debian.master)
-	control_files += $(DEBIAN)/control.d/linux-libc-dev.stub
+	control_files += debian/control.d/linux-libc-dev.stub
 endif
 
 # Calculate Ubuntu Compatible Signing levels