UBUNTU: SAUCE: (no-up) add support for installed header files to ubuntu directory

BugLink: http://bugs.launchpad.net/bugs/684666

We need the aufs headers in the linux-libc-headers, add support for
including files from the ubuntu include directory.
Signed-off-by: Andy Whitcroft <apw@canonical.com>

Makefile

@@ -1070,6 +1070,7 @@ headers_install: __headers
 	  $(error Headers not exportable for the $(SRCARCH) architecture))
 	$(Q)$(MAKE) $(hdr-inst)=include/uapi
 	$(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst)
+	$(Q)$(MAKE) $(hdr-inst)=ubuntu/include dst=include oldheaders=
 
 PHONY += headers_check_all
 headers_check_all: headers_install_all
@@ -1079,6 +1080,7 @@ PHONY += headers_check
 headers_check: headers_install
 	$(Q)$(MAKE) $(hdr-inst)=include/uapi HDRCHECK=1
 	$(Q)$(MAKE) $(hdr-inst)=arch/$(hdr-arch)/include/uapi/asm $(hdr-dst) HDRCHECK=1
+	$(Q)$(MAKE) $(hdr-inst)=ubuntu/include dst=include oldheaders= HDRCHECK=1
 
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