src/console: Add x86 romstage spinlock option and printk spinlock support

This paves the way for AP printk spinlock on AMD platforms

Change-Id: Ice42a0d3177736bf6e1bc601092e413601866f20
Signed-off-by: Timothy Pearson <tpearson@raptorengineeringinc.com>
Reviewed-on: https://review.coreboot.org/11958
Tested-by: Raptor Engineering Automated Test Stand <noreply@raptorengineeringinc.com>
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
4 files changed