parisc: cleanup console handling

* use newly added for_each_console for iterating consoles
* add proper console locking
* do not initialize tmp twice
* no need to declare console_drivers, it's already done in console.h

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>