Use a Raspbian sysroot for armhf-debian builds

This has a newer libc than the linaro toolchain we were using, which is
necessary for using some prebuilt shared objects.

Change-Id: Id4bcf3b1a18300aa40c77cda60050e3987e81dd1
diff --git a/compilers/armhf_debian_rootfs.BUILD b/compilers/armhf_debian_rootfs.BUILD
new file mode 100644
index 0000000..004b82a
--- /dev/null
+++ b/compilers/armhf_debian_rootfs.BUILD
@@ -0,0 +1,15 @@
+filegroup(
+    name = "sysroot_files",
+    srcs = glob(
+        include = [
+            "include/**",
+            "lib/**",
+            "usr/include/**",
+            "usr/lib/**",
+        ],
+        exclude = [
+            "usr/share/**",
+        ],
+    ),
+    visibility = ["//visibility:public"],
+)
diff --git a/compilers/linaro_linux_gcc.BUILD b/compilers/linaro_linux_gcc.BUILD
index aea261d..f2fae98 100644
--- a/compilers/linaro_linux_gcc.BUILD
+++ b/compilers/linaro_linux_gcc.BUILD
@@ -58,14 +58,15 @@
 
 filegroup(
     name = "compiler_pieces",
-    srcs = glob([
-        "arm-linux-gnueabihf/**",
-        "libexec/**",
-        "lib/gcc/arm-linux-gnueabihf/**",
-        "include/**",
-    ], exclude=["arm-linux-gnueabihf/libc/usr/include/linux/sctp.h"]) +
-    [
-        "@org_frc971//third_party/linux:sctp",
+    srcs = glob(
+        include = [
+            "arm-linux-gnueabihf/**",
+            "libexec/**",
+            "lib/gcc/arm-linux-gnueabihf/**",
+            "include/**",
+        ],
+    ) + [
+        "@armhf_debian_rootfs//:sysroot_files",
     ],
 )