constify a bunch of struct file_operations instances

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 80dcc53..b62bd1b 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -1483,7 +1483,7 @@
 	return 0;
 }
 
-static struct file_operations kvm_rma_fops = {
+static const struct file_operations kvm_rma_fops = {
 	.mmap           = kvm_rma_mmap,
 	.release	= kvm_rma_release,
 };