update_kernel: first cut at arm support

remote_access.sh

Index: remote_access.sh
diff --git a/remote_access.sh b/remote_access.sh
index 222fdf7e943399431ffa048a86e0f01d951be3be..bdd9b242adb917a950b72f2fe39f0761c4a1b3c0 100644
--- a/remote_access.sh
+++ b/remote_access.sh
@@ -83,6 +83,17 @@ function wait_with_timeout() {
   ! is_pid_running ${pid}
 }
 
+function learn_arch() {
+  [ -n "${FLAGS_arch}" ] && return
+  remote_sh uname -m
+  FLAGS_arch=$(echo "${REMOTE_OUT}" | sed s/armv7l/arm/g)
+  if [ -z "${FLAGS_arch}" ]; then
+    error "Arch required"
+    exit 1
+  fi
+  info "Target reports arch is ${FLAGS_arch}"
+}
+
 # Checks to see if a machine has rebooted using the presence of a tmp file.
 function check_if_rebooted() {
   local output_file="${TMP}/output"