The directories for objdump is created by the code
a few lines below:

  [ ! -d "$OBJDIFFD/$dn" ] && mkdir -p "$OBJDIFFD/$dn"
Signed-off-by: NMasahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: NJason Cooper <jason@lakedaemon.net>
Signed-off-by: NMichal Marek <mmarek@suse.cz>