compat_ioctl: scsi: move ioctl handling into drivers

Each driver calling scsi_cmd_blk_ioctl() and/or scsi_ioctl() gets
an equivalent compat_ioctl() handler that implements the same
commands by calling scsi_cmd_blk_compat_ioctl()/scsi_compat_ioctl().

With this, we can remove the entries from fs/compat_ioctl.c.
The new code is larger, but should be easier to maintain
and keep updated with newly added commands.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>