Merge "Mark getpagesize() const." am: 48d405ea4b

Original change: https://android-review.googlesource.com/c/platform/bionic/+/2636854

Change-Id: I859c61ff561882f479f5c14a4756bb06bd8f6b6c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>