Fix __DATE__ macro.
Fix __DATE__ macro.

N1570 says __DATE__ is defined as "Mmm dd yyyy", and the first character
of dd is a space character if the value is less than 10. So it shouldn't
be zero-padded.

jtramm/8cc,jtramm/8cc,cpjreynolds/8cc,andrewchambers/8cc,jtramm/8cc,rui314/8cc,abc00/8cc,nobody1986/8cc,8l/8cc,gergo-/8cc,nobody1986/8cc,8l/8cc,cpjreynolds/8cc,gergo-/8cc,rui314/8cc,abc00/8cc,cpjreynolds/8cc,andrewchambers/8cc,rui314/8cc,vastin/8cc,abc00/8cc,andrewchambers/8cc,8l/8cc,jtramm/8cc,vastin/8cc,vastin/8cc,nobody1986/8cc,abc00/8cc,nobody1986/8cc,gergo-/8cc,vastin/8cc,andrewchambers/8cc,8l/8cc,rui314/8cc,cpjreynolds/8cc