improve readability of stdio: fix indentation and remove trailing spaces

Change-Id: Ic51e58a7c75d20bf770dc0ebd7f97a338fbe0036
Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>

libc/stdio/printf.c

@@ -38,10 +38,10 @@ int
 printf(const char *fmt, ...)
 {
 	int ret;
-  va_list ap;
+	va_list ap;
 
 	va_start(ap, fmt);
 	ret = vfprintf(stdout, fmt, ap);
-  va_end(ap);
+	va_end(ap);
 	return (ret);
 }