[SCSI] megaraid: Make megaraid_ioctl() check copy_to_user() return value
Check copy_to_user() return value in drivers/scsi/megaraid.c::megadev_ioctl()
This gets rid of this little warning:
drivers/scsi/megaraid.c:3661: warning: ignoring return value of 'copy_to_user', declared with attribute warn_unused_result