Merge "riscv64: remove some obsolete #if cruft." into main am: df0b557e09

Original change: https://android-review.googlesource.com/c/platform/bionic/+/2896304

Change-Id: I53353a8e4a4fa93f6daf6afcf31b3802e29067f3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>