make_device_config: Fix non-fatal error message with dash and other shells

make_device_config: Fix non-fatal error message with dash and other shells

ORS=" " adds a blank to the name of the include file.
Some shells (e.g. dash) don't accept input redirection
(tr -d '\r' < $f) when $f ends with a blank, so they
print an error message instead of reading pci.mak.
This is a non-fatal error because pci.mak does not
contain an include line. It was introduced by commit
5d6b423c5cd6f9dfac30959ff1d5c088996719c3.

Using printf avoids adding a blank and is also supported
by older awk versions (this solution was suggested by
Paolo Bonzini, thank you).

Cc: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Tested-by: Andreas Färber <andreas.faerber@web.de>