Merge pull request #8605 from theanalyst/fix/15455

rgw: return 503 for requests when master zone is down

Reviewed-by: Casey Bodley <cbodley@redhat.com>

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

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

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

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

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