arm64: add spin table support

There was a hacky and one-off spin table support in tegra132.
Make this support generic for all arm64 chips.

BUG=chrome-os-partner:32082
BRANCH=None
TEST=Ran with and without secure monitor booting smp into the kernel.

Change-Id: I3425ab0c30983d4c74d0aa465dda38bb2c91c83b
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 024dc3f3e5262433a56ed14934db837b5feb1748
Original-Change-Id: If12083a9afc3b2be663d36cfeed10f9b74bae3c8
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/218654
Original-Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: http://review.coreboot.org/9084
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/arch/arm64/boot.c

@@ -21,6 +21,7 @@
 #include <arch/lib_helpers.h>
 #include <arch/secmon.h>
 #include <arch/stages.h>
+#include <arch/spintable.h>
 #include <arch/transition.h>
 #include <cbmem.h>
 #include <console/console.h>
@@ -38,6 +39,9 @@ void arch_payload_run(const struct payload *payload)
 
 	secmon_run(payload_entry, cb_tables);
 
+	/* Start the other CPUs spinning. */
+	spintable_start();
+
 	/* If current EL is not EL3, jump to payload at same EL. */
 	if (current_el != EL3) {
 		cache_sync_instructions();