fix regression from "vsprintf: unify the format decoding layer for its 3 users"

Jeremy Fitzhardinge reported:

> Change fef20d9c, "vsprintf:
> unify the format decoding layer for its 3 users", causes a
> regression in xenbus which results in no devices getting
> attached to a new domain.

%.*s is broken - fix it.
Reported-by: NJeremy Fitzhardinge <jeremy@goop.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

lib/vsprintf.c

@@ -843,7 +843,7 @@ static int format_decode(const char *fmt, struct printf_spec *spec)
 				spec->precision = 0;
 		} else if (*fmt == '*') {
 			/* it's the next argument */
-			spec->type = FORMAT_TYPE_WITDH;
+			spec->type = FORMAT_TYPE_PRECISION;
 			return ++fmt - start;
 		}
 	}