tegra124: Add the tegra124 compatibility string to crossystem.

Teach crossystem the tegra124 compatibility string so that it can identify the
platform for tegra124 based systems.

I called the platform Tegra5 to fit in with what seems to be the naming scheme
for the other Tegra SOCs.

BUG=chrome-os-partner:25355
TEST=Built and ran on nyan and saw the "platform_family" setting return Tegra5
instead of (error).
BRANCH=None

Change-Id: I1044f958ecdac37ad285fdc3d53e7bc36ca69315
Signed-off-by: Gabe Black <gabeblack@google.com>
Reviewed-on: https://chromium-review.googlesource.com/184051
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Tested-by: Gabe Black <gabeblack@chromium.org>
Commit-Queue: Gabe Black <gabeblack@chromium.org>
diff --git a/host/arch/arm/lib/crossystem_arch.c b/host/arch/arm/lib/crossystem_arch.c
index b5422de..513539d 100644
--- a/host/arch/arm/lib/crossystem_arch.c
+++ b/host/arch/arm/lib/crossystem_arch.c
@@ -54,6 +54,7 @@
 
 /* Array of platform family names, terminated with a NULL entry */
 const PlatformFamily platform_family_array[] = {
+  {"nvidia,tegra124", "Tegra5"},
   {"nvidia,tegra250", "Tegra2"},
   {"nvidia,tegra20", "Tegra2"},
   {"ti,omap4", "OMAP4"},