i2c: dev: Add __user annotation

Fix Sparse warnings:
drivers/i2c/i2c-dev.c:546:19: warning: incorrect type in assignment (different address spaces)
drivers/i2c/i2c-dev.c:549:53: warning: incorrect type in argument 2 (different address spaces)

compat_ptr() returns a pointer tagged __user which gets assigned to a
pointer missing the __user annotation. The same pointer is passed to
copy_from_user() as an argument where it is expected to have the __user
annotation. Fix both by adding the __user annotation to the pointer.

Fixes: 7d5cb456 ("i2c compat ioctls: move to ->compat_ioctl()")
Signed-off-by: Andreas Hecht <andreas.e.hecht@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

drivers/i2c/i2c-dev.c

@@ -526,7 +526,7 @@ static long compat_i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned lo
 		return put_user(funcs, (compat_ulong_t __user *)arg);
 	case I2C_RDWR: {
 		struct i2c_rdwr_ioctl_data32 rdwr_arg;
-		struct i2c_msg32 *p;
+		struct i2c_msg32 __user *p;
 		struct i2c_msg *rdwr_pa;
 		int i;