makefile: Add VB ATTEST and OSVERSION IN BOOTIMAGE flags

VB ATTEST flag is needed for latest version of verified boot
and OSVERSION IN BOOTIMAGE is needed for storing os version
in bootimage header structure.

Change-Id: I3b6d09786f8c1071f6fcf9cc4bdbddbfa8923f70
diff --git a/AndroidBoot.mk b/AndroidBoot.mk
index 33f6e91..85c917d 100644
--- a/AndroidBoot.mk
+++ b/AndroidBoot.mk
@@ -27,6 +27,14 @@
   VERIFIED_BOOT := VERIFIED_BOOT=0
 endif
 
+ifeq (1,$(filter 1,$(shell echo "$$(( $(PLATFORM_SDK_VERSION) >= 24 ))" )))
+  OSVERSION_IN_BOOTIMAGE := OSVERSION_IN_BOOTIMAGE=1
+  ENABLE_VB_ATTEST := ENABLE_VB_ATTEST=1
+else
+  OSVERSION_IN_BOOTIMAGE := OSVERSION_IN_BOOTIMAGE=0
+  ENABLE_VB_ATTEST := ENABLE_VB_ATTEST=0
+endif
+
 ifneq ($(TARGET_BUILD_VARIANT),user)
   DEVICE_STATUS := DEFAULT_UNLOCK=true
 endif
@@ -55,7 +63,7 @@
 # ELF binary for ABOOT
 TARGET_ABOOT_ELF := $(PRODUCT_OUT)/aboot.elf
 $(TARGET_ABOOT_ELF): ABOOT_CLEAN | $(ABOOT_OUT)
-	$(MAKE) -C bootable/bootloader/lk TOOLCHAIN_PREFIX=$(CROSS_COMPILE) BOOTLOADER_OUT=../../../$(ABOOT_OUT) $(BOOTLOADER_PLATFORM) $(EMMC_BOOT) $(SIGNED_KERNEL) $(VERIFIED_BOOT) $(DEVICE_STATUS) $(BUILD_VARIANT) $(BOARD_NAME)
+	$(MAKE) -C bootable/bootloader/lk TOOLCHAIN_PREFIX=$(CROSS_COMPILE) BOOTLOADER_OUT=../../../$(ABOOT_OUT) $(BOOTLOADER_PLATFORM) $(EMMC_BOOT) $(SIGNED_KERNEL) $(VERIFIED_BOOT) $(DEVICE_STATUS) $(BUILD_VARIANT) $(BOARD_NAME) $(ENABLE_VB_ATTEST) $(OSVERSION_IN_BOOTIMAGE)
 
 # NAND variant output
 TARGET_NAND_BOOTLOADER := $(PRODUCT_OUT)/appsboot.mbn