ssb: Remove home-grown printk wrappers

Replace the ssb printk wrappers by standard print helpers.
Also remove SSB_SILENT. Nobody should use it anyway.

Originally submitted by Joe Perches <joe@perches.com>.
Modified to add dev_... based printks.

Signed-off-by: Michael Buesch <m@bues.ch>
Tested-by: Michael Buesch <m@bues.ch>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>