fix failure of wide printf/scanf functions to set wide orientation

in some cases, these functions internally call a byte-based input or
output function before calling getwc/putwc, so they cannot rely on the
latter to set the orientation.

(cherry picked from commit 984c25b74da085c6ae6b44a87bbd5f8afc9be331)

src/stdio/vfwprintf.c

@@ -355,6 +355,7 @@ int vfwprintf(FILE *restrict f, const wchar_t *restrict fmt, va_list ap)
 	}
 
 	FLOCK(f);
+	f->mode |= f->mode+1;
 	ret = wprintf_core(f, fmt, &ap2, nl_arg, nl_type);
 	FUNLOCK(f);
 	va_end(ap2);

src/stdio/vfwscanf.c

@@ -104,6 +104,8 @@ int vfwscanf(FILE *restrict f, const wchar_t *restrict fmt, va_list ap)
 
 	FLOCK(f);
 
+	f->mode |= f->mode+1;
+
 	for (p=fmt; *p; p++) {
 
 		alloc = 0;