Merge pull request #8053 from rzarzynski/wip-rgw-aws4-memalloc

rgw: improve memory management in AWS4 auth
Reviewed-by: Orit Wasserman <owasserm@redhat.com>

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

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

diff --cc src/rgw/rgw_rest_s3.cc
Simple merge