Androidboot: Pass compile time argument for PM660.

Pass compile time flag to enable PM660 support.

Change-Id: I6949bea3faeb0de5e648c0ba0d5339c2a4e01399
diff --git a/AndroidBoot.mk b/AndroidBoot.mk
index b0a1427..89cbfd0 100644
--- a/AndroidBoot.mk
+++ b/AndroidBoot.mk
@@ -124,7 +124,7 @@
 
 # Top level for eMMC variant targets
 $(TARGET_EMMC_BOOTLOADER): emmc_appsbootldr_clean | $(EMMC_BOOTLOADER_OUT) $(INSTALLED_KEYSTOREIMAGE_TARGET)
-	$(MAKE) -C $(LK_PATH) TOOLCHAIN_PREFIX=$(CROSS_COMPILE) BOOTLOADER_OUT=$(CROOT_DIR)/$(EMMC_BOOTLOADER_OUT) $(BOOTLOADER_PLATFORM) EMMC_BOOT=1 $(SIGNED_KERNEL) $(VERIFIED_BOOT) $(ENABLE_DISPLAY) $(ENABLE_BOOTDEVICE_MOUNT) $(DEVICE_STATUS) $(BUILD_VARIANT) $(BOARD_NAME) $(ENABLE_VB_ATTEST) $(OSVERSION_IN_BOOTIMAGE)
+	$(MAKE) -C $(LK_PATH) TOOLCHAIN_PREFIX=$(CROSS_COMPILE) BOOTLOADER_OUT=$(CROOT_DIR)/$(EMMC_BOOTLOADER_OUT) $(BOOTLOADER_PLATFORM) EMMC_BOOT=1 $(SIGNED_KERNEL) $(VERIFIED_BOOT) $(ENABLE_DISPLAY) $(ENABLE_BOOTDEVICE_MOUNT) $(DEVICE_STATUS) $(BUILD_VARIANT) $(BOARD_NAME) $(ENABLE_VB_ATTEST) $(OSVERSION_IN_BOOTIMAGE) $(ENABLE_BG_SUPPORT)
 
 # Keep build NAND & eMMC as default for targets still using TARGET_BOOTLOADER
 TARGET_BOOTLOADER := $(PRODUCT_OUT)/EMMCBOOT.MBN