configure: don't accidentally set @LIBTOOL@ to 'yes'
configure: don't accidentally set @LIBTOOL@ to 'yes'

Substituting @LIBTOOL@ with 'yes' would result in a lot of console
output (34 GB in my case, before SIGKILL), without getting anything
compiled at all.

Signed-off-by: Roland Hieber <48794882845d4fbc9188db1d2a1934c8aae80fcc@pengutronix.de>

apple/cups,apple/cups,OpenPrinting/cups,OpenPrinting/cups,OpenPrinting/cups,apple/cups,apple/cups,OpenPrinting/cups