openrisc/uaccess: fix sparse errors

virtio wants to read bitwise types from userspace using get_user. At the
moment this triggers sparse errors, since the value is passed through an
integer.

Fix that up using __force.

Signed-off-by: Michael S. Tsirkin <[e-mail]>

arch/openrisc/include/asm/uaccess.h

···
 ({								\
 	long __gu_err, __gu_val;				\
 	__get_user_size(__gu_val, (ptr), (size), __gu_err);	\
-	(x) = (__typeof__(*(ptr)))__gu_val;			\
+	(x) = (__force __typeof__(*(ptr)))__gu_val;		\
 	__gu_err;						\
 })
 
···
 	const __typeof__(*(ptr)) * __gu_addr = (ptr);			\
 	if (access_ok(VERIFY_READ, __gu_addr, size))			\
 		__get_user_size(__gu_val, __gu_addr, (size), __gu_err);	\
-	(x) = (__typeof__(*(ptr)))__gu_val;				\
+	(x) = (__force __typeof__(*(ptr)))__gu_val;			\
 	__gu_err;							\
 })