Merge pull request #25450 from ivancich/wip-rgw-category-cleanup

rgw: clean-up -- use enum class for stats category

Reviewed-by: Matt Benjamin <mbenjami@redhat.com>

diff --cc src/cls/rgw/cls_rgw_client.cc
Simple merge

diff --cc src/cls/rgw/cls_rgw_client.h
Simple merge

diff --cc src/cls/rgw/cls_rgw_ops.h
Simple merge

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

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

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

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

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