[PATCH] x86: fix build race when generating temporary object files (take 2)

[Jan Beulich <jbeulich@xxxxxxxx>]

The original commit wasn't quite sufficient: Emptying DEPS is helpful
only when nothing will get added to it subsequently. xen/Rules.mk will,
after including the local Makefile, amend DEPS by dependencies for
objects living in sub-directories though. For the purpose of suppressing
dependencies of the makefiles on the .*.d2 files (and thus to avoid
their re-generation) it is, however, not necessary at all to play with
DEPS. Instead we can override DEPS_INCLUDE (which generally is a late-
expansion variable).

Fixes: 761bb575ce97 ("x86: fix build race when generating temporary object 
files")
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -314,5 +314,5 @@ clean::
 # Suppress loading of DEPS files for internal, temporary target files.  This
 # then also suppresses re-generation of the respective .*.d2 files.
 ifeq ($(filter-out .xen%.o,$(notdir $(MAKECMDGOALS))),)
-DEPS:=
+DEPS_INCLUDE:=
 endif