hg: shenandoah/jdk: Fix compilation errors after jdk-14+17 merge

[zgu at redhat.com]

Changeset: d29bfa3c2e2a
Author:    zgu
Date:      2019-10-04 17:36 -0400
URL:       https://hg.openjdk.java.net/shenandoah/jdk/rev/d29bfa3c2e2a

Fix compilation errors after jdk-14+17 merge
Reviewed-by: rkennke

! src/hotspot/share/gc/shenandoah/shenandoahBarrierSetNMethod.cpp
! src/hotspot/share/gc/shenandoah/shenandoahCodeRoots.cpp