When building mesa without X11 enabled, and disabling dri package config,
the enforced "--enable-gbm" fails building mesa, because this feature
requires "--enable-dri", too - which has been disabled by package config.
Consequently, when gbm requires dri, --disable-dri causes in --disable-gbm,
which makes explicit --disable-gbm in case of --disable-dri redundant.
Signed-off-by: Jens Rehsack <sno@netbsd.org> Signed-off-by: Ross Burton <ross.burton@intel.com>
