[aarch64-port-dev ] RFR: UseBiasedLocking should be disabled only for Shenandoah

[Aleksey Shipilev]

http://cr.openjdk.java.net/~shade/shenandoah/8u-int-biased/webrev.01/

This is a major gaffe in current aarch64-port/shenandoah-8u. We should disable UseBiasedLocking only
when Shenandoah is enabled. But the block that does it is misplaced in check_gclog_consistency(),
while it should be in set_shenandoah_gc_flags(). This does not affect our sh/jdk8u development repo,
because we removed that block altogether, but we cannot wait for another Shenandoah integration to
fix this.

Testing: manual runs with -XX:+PrintFlagsFinal

-Aleksey