V4L/DVB (3667b): cpia2: fix function prototype

Fix address space warning (from sparse):
drivers/media/video/cpia2/cpia2_core.c:2355:6: error: symbol 'cpia2_read' redeclared with different type (originally declared at drivers/media/video/cpia2/cpia2.h:458) - incompatible argument 2 (different address spaces)
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/cpia2/cpia2.h

@@ -456,7 +456,7 @@ int cpia2_init_camera(struct camera_data *cam);
 int cpia2_allocate_buffers(struct camera_data *cam);
 void cpia2_free_buffers(struct camera_data *cam);
 long cpia2_read(struct camera_data *cam,
-		char *buf, unsigned long count, int noblock);
+		char __user *buf, unsigned long count, int noblock);
 unsigned int cpia2_poll(struct camera_data *cam,
 			struct file *filp, poll_table *wait);
 int cpia2_remap_buffer(struct camera_data *cam, struct vm_area_struct *vma);