misc: only build with lto if explicitly enabled

Change the LTO default to off from probe because it wastes build time on
developer machines.  Anyone who really wants it for release builds or
whatever can still turn it on.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

1 file changed