coverity: fix issues detected in recent code

coverity: fix issues detected in recent code

Uninitialized variables  (UNINIT) /safe/guest2/covscan/LVM2.2.02.158/tools/toollib.c: 3520 in _process_pvs_in_vgs()
Uninitialized variables  (UNINIT) Using uninitialized value "do_report_ret_code".

Null pointer dereferences  (REVERSE_INULL) /safe/guest2/covscan/LVM2.2.02.158/libdm/libdm-report.c: 4745 in dm_report_output()
Null pointer dereferences  (REVERSE_INULL) Null-checking "rh" suggests that it may be null, but it has already been dereferenced on all paths leading to the check.

Incorrect expression  (MISSING_COMMA) /safe/guest2/covscan/LVM2.2.02.158/lib/log/log.c: 280 in _get_log_level_name()
Incorrect expression  (MISSING_COMMA) In the initialization of "log_level_names", a suspicious concatenated string ""noticeinfo"" is produced.

Null pointer dereferences  (FORWARD_NULL) /safe/guest2/covscan/LVM2.2.02.158/tools/reporter.c: 816 in_get_report_options()
Null pointer dereferences  (FORWARD_NULL) Comparing "mem" to null implies that "mem" might be null.