Consolitate all the AP core startup stuff under a single #ifdef SMP block.
Remove some other ifdefs that came in with a copy/paste that mean basically
"if this processor supports multicore stuff", because if you're starting up
an AP core... it does.
Fix the incorrect handling of %b and \c in printf(1)

This is required for POSIX compliance.

Obtained from:	Garrett D'Amore (Illumos)
MFC after:	4 days