Use the downloaded clang when building for armhf-debian

This makes it work on a barebones Stretch installation.

Also add building for this CPU to the CI script so we know it keeps
working, which means marking everything that's supposed to work
appropriately.

Change-Id: Ic050ce20eae45c6b23e0e42dddb24db3ebc70b84
diff --git a/aos/linux_code/ipc_lib/BUILD b/aos/linux_code/ipc_lib/BUILD
index d5d2c8d..289bde8 100644
--- a/aos/linux_code/ipc_lib/BUILD
+++ b/aos/linux_code/ipc_lib/BUILD
@@ -8,6 +8,9 @@
     hdrs = [
         "aos_sync.h",
     ],
+    compatible_with = [
+        "//tools:armhf-debian",
+    ],
     linkopts = [
         "-lpthread",
     ],
@@ -27,6 +30,9 @@
     hdrs = [
         "core_lib.h",
     ],
+    compatible_with = [
+        "//tools:armhf-debian",
+    ],
     deps = [
         ":aos_sync",
         ":shared_mem_types",
@@ -41,6 +47,9 @@
     hdrs = [
         "shared_mem.h",
     ],
+    compatible_with = [
+        "//tools:armhf-debian",
+    ],
     linkopts = [
         "-lrt",
     ],
@@ -59,6 +68,9 @@
     hdrs = [
         "shared_mem_types.h",
     ],
+    compatible_with = [
+        "//tools:armhf-debian",
+    ],
     deps = [
         ":aos_sync",
     ],
@@ -72,6 +84,9 @@
     hdrs = [
         "queue.h",
     ],
+    compatible_with = [
+        "//tools:armhf-debian",
+    ],
     linkopts = [
         "-lrt",
     ],
@@ -109,6 +124,9 @@
     srcs = [
         "ipc_stress_test.cc",
     ],
+    compatible_with = [
+        "//tools:armhf-debian",
+    ],
     tags = [
         "manual",
     ],