[14] RFR (S) 8244740: Shenandoah: rename ShenandoahNormalMode to ShenandoahSATBMode

[Aleksey Shipilev]

Original RFE:
  https://bugs.openjdk.java.net/browse/JDK-8244740
  https://hg.openjdk.java.net/jdk/jdk/rev/9fb4e20c6975

Once again, context is a bit different, so I re-made the actual rename, and applied the rest of the
hunks automatically. 14u webrev:
  https://cr.openjdk.java.net/~shade/8244740/webrev.01/

Testing: hotspot_gc_shenandoah {fastdebug,release}

-- 
Thanks,
-Aleksey