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/gadget/printer.c b/drivers/usb/gadget/printer.c
index 2950015..2d867fd 100644
--- a/drivers/usb/gadget/printer.c
+++ b/drivers/usb/gadget/printer.c
@@ -875,7 +875,7 @@
 }
 
 /* used after endpoint configuration */
-static struct file_operations printer_io_operations = {
+static const struct file_operations printer_io_operations = {
 	.owner =	THIS_MODULE,
 	.open =		printer_open,
 	.read =		printer_read,