init: Write the reason in BCB on "reboot recovery"

Without this change "adb reboot recovery" leads to normal boot.

Change-Id: I361d0a1f6f6f2c57f3dc80102c21970b462c9b9c
Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
diff --git a/init/reboot.cpp b/init/reboot.cpp
index d9d885c..0bb0115 100644
--- a/init/reboot.cpp
+++ b/init/reboot.cpp
@@ -671,6 +671,13 @@
                                   "bootloader_message: "
                                << err;
                 }
+            } else if (reboot_target == "recovery") {
+                const std::vector<std::string> options = {};
+                std::string err;
+                if (!write_bootloader_message(options, &err)) {
+                    LOG(ERROR) << "Failed to set bootloader message: " << err;
+                    return false;
+                }
             } else if (reboot_target == "sideload" || reboot_target == "sideload-auto-reboot" ||
                        reboot_target == "fastboot") {
                 std::string arg = reboot_target == "sideload-auto-reboot" ? "sideload_auto_reboot"