Log Message:
-----------
locale.c: Don't compile ALT_DIGITS code if not reached
We know in some cases that a platform won't ever execute the code to
compute ALT_DIGITS. Windows and OpenBSD are two examples. Windows
because it doesn't support the strftime() %O modifier; OpenBSD because
the LC_TIME locale can only ever be C, which has no ALT_DIGITS.
In such cases, we can skip compiling the ALT_DIGIT code.