fix quoting in makeabs()

'local' is treated as a command, so its arguments need to be quoted,
unlike in a real variable assignment.

amends 4b557751

.

Change-Id: I5a4c929e52e2344a6129c8e9dd4c0c80cd408ff0
Reviewed-by: Joerg Bornemann <joerg.bornemann@theqtcompany.com>