log: print dummy timestamp if localtime call fails
log: print dummy timestamp if localtime call fails

Handle the case where localtime fails (NULL) and print
something else to indicate localtime is erroneous.

Signed-off-by: U. Artie Eoff <32aece0d55055227b44d04b7d0051cf3d04ee871@intel.com>

Gnurou/weston,Fantu/compositor-spice,Fantu/compositor-spice,giucam/weston,xorgy/weston,Fantu/compositor-spice,udoprog/weston,Tarnyko/weston-xdg_surface_present,xorgy/weston,jonnylamb/weston,Gnurou/weston,mchalupa/weston,sir-murray/weston,krezovic/weston,jonnylamb/weston,eyolfson/weston,eyolfson/weston,krezovic/weston,udoprog/weston,giucam/weston,sir-murray/weston,Tarnyko/weston-xdg_surface_present,mchalupa/weston,kwm81/weston,kwm81/weston