We should never zero-pad INF or NaN (yielding silly strings like "00inf")

even if the programmer asks for zero padding.

lib/libc/stdio/vfprintf.c

@@ -908,6 +908,7 @@ reswitch:	switch (ch) {
 				} else
 					cp = (ch >= 'a') ? "inf" : "INF";
 				size = 3;
+				flags &= ~ZEROPAD;
 				break;
 			}
 			flags |= FPT;