[XEN PATCH v5 12/16] xen/build: Use if_changed for prelink*.o

[Anthony PERARD <anthony.perard@xxxxxxxxxx>]

We change the dependencies of prelink-efi.o so that we can use the
same command line. The dependency on efi/built_in.o isn't needed
because, we already have:
    efi/*.o: efi/built_in.o
to build efi/*.o files that prelink-efi.o needs.

Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
Reviewed-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
---

Notes:
    v4:
    - fix rebuild, prelink.o and prelink-efi.o needs to be in targets

 xen/arch/x86/Makefile | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile
index 92430192a74e..33e9ebf25074 100644
--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -128,11 +128,13 @@ prelink.o: $(patsubst 
%/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink_lto.o
 prelink-efi.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) 
prelink-efi_lto.o efi/boot.init.o
        $(LD) $(XEN_LDFLAGS) -r -o $@ $^
 else
-prelink.o: $(ALL_OBJS)
-       $(LD) $(XEN_LDFLAGS) -r -o $@ $^
+prelink.o: $(ALL_OBJS) FORCE
+       $(call if_changed,ld)
+
+prelink-efi.o: $(filter-out %/efi/built_in.o,$(ALL_OBJS)) efi/boot.init.o 
efi/runtime.o efi/compat.o FORCE
+       $(call if_changed,ld)
 
-prelink-efi.o: $(ALL_OBJS) efi/boot.init.o efi/runtime.o efi/compat.o
-       $(LD) $(XEN_LDFLAGS) -r -o $@ $(filter-out %/efi/built_in.o,$^)
+targets += prelink.o prelink-efi.o
 endif
 
 $(TARGET)-syms: prelink.o xen.lds
-- 
Anthony PERARD