mon: refuse "mon remove" if only one mon left

Fixes: #4439
Signed-off-by: Dan Mick <dan.mick@inktank.com>
client/SyntheticClient.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
common/lockdep.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
crush/CrushCompiler.cc: prefer prefix --operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
crush/CrushWrapper.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
key_value_store/cls_kvs.cc: prefer prefix --operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
kv_flat_btree_async.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
libcephfs.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
librados/IoCtxImpl.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
librados/RadosClient.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
librbd/ImageCtx.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
librbd/internal.cc: prefer prefix ++operator for iterators

Prefer prefix ++operator for iterators, move iterator declaration into
the related for loop.

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mds/AnchorClient.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mds/AnchorServer.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mds/AnchorServer.h: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mds/CDir.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mds/CInode.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mds/MDCache.h: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mds/Locker.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mds/MDBalancer.cc: prefer prefix ++operator for iterators

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>