recovery: Display recovery version

Set the title lines to the lineage version and build date and render
them between the logo and menu.

The "Lineage Recovery" and "Android Fastboot" lines are removed
because the logo already says "Recovery" or "Fastbootd".

Also: Assume the logo and back icon are non-null.
ScreenRecoveryUI::SelectMenu already makes this assumption, and it
avoids questions about how to handle "back" if either the logo or
the back icon is null.

Change-Id: I63bb23e34e52fdb01dd85e793552aa259f46a7de
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index a093008..d905093 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -39,7 +39,7 @@
 Device::BuiltinAction StartFastboot(Device* device, const std::vector<std::string>& /* args */) {
   RecoveryUI* ui = device->GetUI();
 
-  std::vector<std::string> title_lines = { "Android Fastboot" };
+  std::vector<std::string> title_lines;
   title_lines.push_back("Product name - " + android::base::GetProperty("ro.product.device", ""));
   title_lines.push_back("Bootloader version - " + android::base::GetProperty("ro.bootloader", ""));
   title_lines.push_back("Baseband version - " +