Call time() only once during mainloop

[michaelortmann]

Found by: michaelortmann
Patch by: michaelortmann
Fixes:

One-line summary:
Call time() only once during mainloop() and core_secondly()

Additional description (if needed):
found with ltrace

Test cases demonstrating functionality (if applicable):
$ ltrace ./eggdrop -t BotA.conf
Before:

time(0)                                                                        = 1701307982
time(0)                                                                        = 1701307982

After:
time(0) = 1701308015