Make ieee1394_init a fs-initcall

Make ieee1394_init a fs-initcall

It needs to happen before any firewire driver actually registers itself,
and that was previously handled by having the Makefile list the core
ieee1394 files before the drivers.

But now there are firewire drivers in drivers/media, and the Makefile
games aren't enough.  So just make ieee1394_init happen earlier in the
init sequence, the way all other bus layers already do.

Reported-and-tested-by: Ingo Molnar <mingo@elte.hu>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Henrik Kurelid <henrik@kurelid.se>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Ben Backx <ben@bbackx.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>