Fixed possible use of old cached times if runtime went backwards. If ngx_time_sigsafe_update() updated only ngx_cached_err_log_time, and then clock was adjusted backwards, the cached_time[slot].sec might accidentally match current seconds on next ngx_time_update() call, resulting in various cached times not being updated. Fix is to clear the cached_time[slot].sec to explicitly mark cached times are stale and need updating.

# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


ngx_include="unistd.h";      . auto/include
ngx_include="inttypes.h";    . auto/include
ngx_include="limits.h";      . auto/include
ngx_include="sys/filio.h";   . auto/include
ngx_include="sys/param.h";   . auto/include
ngx_include="sys/mount.h";   . auto/include
ngx_include="sys/statvfs.h"; . auto/include
ngx_include="crypt.h";       . auto/include