Clean up some of our command line code:

- We were copying the command line out of the device tree twice, but the
  first time we forgot to add CONFIG_CMDLINE. Fix this and remove the
  second copy.
- The command line birec code ran after we had done some command line
  parsing in prom.c. This had the opportunity to really confuse the
  user, with some options being parsed out of the device tree and the
  other out of birecs. Luckily we could find no user of the command
  line birecs, so remove them.
- remove duplicate printing of kernel command line;
- clean up iseries inits and create an iSeries_parse_cmdline.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>