compat_ioctl: ignore RAID_VERSION ioctl

md ioctls are now handled by the md driver itself, but mdadm
may call RAID_VERSION on other devices as well. Mark the command
as IGNORE_IOCTL so this fails silently rather than printing
an annoying message.

Reported-by: "Michael S. Tsirkin" <[e-mail]>
Cc: "Rafael J. Wysocki" <[e-mail]>
Signed-off-by: Arnd Bergmann <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

fs/compat_ioctl.c

···
 #ifdef CONFIG_BLOCK
 /* loop */
 IGNORE_IOCTL(LOOP_CLR_FD)
+/* md calls this on random blockdevs */
+IGNORE_IOCTL(RAID_VERSION)
 /* SG stuff */
 COMPATIBLE_IOCTL(SG_SET_TIMEOUT)
 COMPATIBLE_IOCTL(SG_GET_TIMEOUT)