add arm-none-eabi toolchain for boards w/our EC

Boards that build the CrOS EC need this toolchain.  Previously they were
relying on it existing in the SDK by way of link, but as we change the
sdk to not install all toolchains by default, these boards need to pull
in the ones they use explicitly.

BUG=chromium:342199
TEST=building these boards works w/new sdk

Change-Id: Ibe4991981769a5539c5c5fa117a2b5e25f8ce333
Reviewed-on: https://chromium-review.googlesource.com/229992
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
diff --git a/overlay-quawks/toolchain.conf b/overlay-quawks/toolchain.conf
index 932b2b2..6fc54f6 100644
--- a/overlay-quawks/toolchain.conf
+++ b/overlay-quawks/toolchain.conf
@@ -2,3 +2,6 @@
 
 # This is needed to build the target firmware
 i686-pc-linux-gnu
+
+# This is needed to build the EC firmware
+arm-none-eabi
diff --git a/overlay-wolf/toolchain.conf b/overlay-wolf/toolchain.conf
index 932b2b2..6fc54f6 100644
--- a/overlay-wolf/toolchain.conf
+++ b/overlay-wolf/toolchain.conf
@@ -2,3 +2,6 @@
 
 # This is needed to build the target firmware
 i686-pc-linux-gnu
+
+# This is needed to build the EC firmware
+arm-none-eabi