x86/um: fix vDSO installation

The generic vDSO installation logic used by 'make vdso_install' requires
that $(vdso-install-y) is defined by the top-level architecture Makefile
and that it contains a path relative to the root of the tree.
For UML neither of these is satisfied.

Move the definition of $(vdso-install-y) to a place which is included by
the arch/um/Makefile and use the full relative path.

Fixes: f1c2bb8 ("um: implement a x86_64 vDSO")
Signed-off-by: Thomas Weißschuh <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Johannes Berg <[email protected]>

Author: t-8ch

arch/x86/Makefile.um

@@ -60,4 +60,6 @@ ELF_FORMAT := elf64-x86-64
 LINK-$(CONFIG_LD_SCRIPT_DYN_RPATH) += -Wl,-rpath,/lib64
 LINK-y += -m64
 
+vdso-install-y += arch/x86/um/vdso/vdso.so.dbg
+
 endif

arch/x86/um/vdso/Makefile

@@ -3,8 +3,6 @@
 # Building vDSO images for x86.
 #
 
-vdso-install-y += vdso.so
-
 # files to link into the vdso
 vobjs-y := vdso-note.o um_vdso.o