Removed default configuration behavior.
Removed default configuration behavior.

Details:
- Changed the configure script so that it no longer defaults to the
  reference configuration. This change is being made so that the
  developer has a firm awareness of which configuration is being used
  to configure BLIS. Thanks to Mike Kistler and Bryan Marker for this
  suggested change.

rwl/blis,audiofilter/blis,xianyi/blis,audiofilter/blis,rwl/blis,scibuilder/blis,scibuilder/blis,arm-hpc/blis,arm-hpc/blis,scibuilder/blis,scibuilder/blis,arm-hpc/blis,audiofilter/blis,audiofilter/blis,arm-hpc/blis,xianyi/blis,rwl/blis,xianyi/blis,xianyi/blis,rwl/blis