Merge pull request #17972 from cbodley/wip-21401

auth: keep /dev/urandom open for get_random_bytes

Reviewed-by: Adam Emerson <aemerson@redhat.com>

diff --cc CMakeLists.txt
Simple merge

diff --cc src/common/ceph_context.cc
Simple merge

diff --cc src/msg/async/AsyncConnection.cc
Simple merge

diff --cc src/msg/async/AsyncConnection.h
Simple merge

diff --cc src/rgw/rgw_common.cc
Simple merge

diff --cc src/rgw/rgw_common.h
Simple merge

diff --cc src/rgw/rgw_crypt.cc
Simple merge

diff --cc src/rgw/rgw_lc.cc
Simple merge

diff --cc src/rgw/rgw_user.cc
Simple merge