drivers/char: Add module.h to those who were using it implicitly

A pending cleanup will mean that module.h won't be implicitly
everywhere anymore. Make sure the modular drivers in char are
actually calling out for <module.h> explicitly in advance.

Signed-off-by: Paul Gortmaker <[e-mail]>

drivers/char/hw_random/virtio-rng.c

···
 #include <linux/spinlock.h>
 #include <linux/virtio.h>
 #include <linux/virtio_rng.h>
+#include <linux/module.h>
 
 static struct virtqueue *vq;
 static unsigned int data_avail;

drivers/char/ps3flash.c

···
 #include <linux/miscdevice.h>
 #include <linux/slab.h>
 #include <linux/uaccess.h>
+#include <linux/module.h>
 
 #include <asm/lv1call.h>
 #include <asm/ps3stor.h>

drivers/char/virtio_console.c

···
 #include <linux/virtio_console.h>
 #include <linux/wait.h>
 #include <linux/workqueue.h>
+#include <linux/module.h>
 #include "../tty/hvc/hvc_console.h"
 
 /*