mds/MDCache.cc: prefer prefix ++operator for iterator

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

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
key_value_store/kv_flat_btree_async.cc: fix some reassign before use value issues

Fix some cases of "(performance) Variable 'err' is reassigned a
value before the old one has been used." issues from cppcheck.

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
kv_flat_btree_async.cc: fix assigned but unused value issue

Fix "Variable 'r' is assigned a value that is never used." issue from
cppcheck. Check return value and print warning if in verbose mode.

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mds/Migrator.cc: reduce scope of 'in' in handle_export_prep()

Reduce scope of 'CInode *in' since it's the way it's done already
in other paths of the function.

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mount/mount.ceph.c: reduce scope of 'value'

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
mds/MDCache.cc: reduce scope of 'CDir *dir' in _create_system_file_finish()

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
fusetrace_ll.cc: handle return value of fuse_session_loop()

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
Merge pull request #343 from dalgaaf/wip-da-SCA-cppcheck

Reviewed-by: Sage Weil <sage@inktank.com>