PL2: Replace bootloader button with download button

BoardConfig.mk

@@ -89,6 +89,8 @@ TW_SCREEN_BLANK_ON_BOOT := true
 TW_THEME := portrait_hdpi
 TW_USE_TOOLBOX := true
 TW_INCLUDE_REPACKTOOLS := true
+TW_NO_REBOOT_BOOTLOADER := true
+TW_HAS_DOWNLOAD_MODE := true
 
 # Workaround for error copying vendor files to recovery ramdisk
 TARGET_COPY_OUT_VENDOR := system/vendor