const: constify remaining file_operations

[akpm@linux-foundation.org: fix KVM]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index 333ee02..864f0ba 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -993,7 +993,7 @@
 	return retval;
 }
 
-static struct file_operations fops = {
+static const struct file_operations fops = {
 	.owner		= THIS_MODULE,
 	.read		= usbtmc_read,
 	.write		= usbtmc_write,