The vDSO needs to have a unique build id in a similar manner
to the kernel and modules. Use the build salt macro.
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NLaura Abbott <labbott@redhat.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>