AndroidBoot.mk: adjust for PATH changes in Android Q

$(MAKE) isn't valid anymore, so use $(KERNEL_MAKE_CMD) instead.

Additionally we need to provide the full path to the compiler, as gcc
isn't present in the PATH anymore

This commit only touches the targets for the make targets that are
actually used.

Issue: FP2A10-18
Change-Id: I3eae6cf1ff0dcb33487e64da87dfcaf9249464ea
diff --git a/AndroidBoot.mk b/AndroidBoot.mk
index 696de17..9765ebe 100644
--- a/AndroidBoot.mk
+++ b/AndroidBoot.mk
@@ -82,7 +82,7 @@
 
 # Top level for eMMC variant targets
 $(TARGET_EMMC_BOOTLOADER): $(emmc_appsbootldr_clean) | $(EMMC_BOOTLOADER_OUT) $(INSTALLED_KEYSTOREIMAGE_TARGET)
-	$(MAKE) -C bootable/bootloader/lk TOOLCHAIN_PREFIX=$(CROSS_COMPILE) BOOTLOADER_OUT=../../../$(EMMC_BOOTLOADER_OUT) $(BOOTLOADER_PLATFORM) EMMC_BOOT=1 $(SIGNED_KERNEL) $(VERIFIED_BOOT) $(DEVICE_STATUS)
+	$(KERNEL_MAKE_CMD) -C bootable/bootloader/lk COMPILER=$(KERNEL_HOST_TOOLCHAIN_ROOT)gcc TOOLCHAIN_PREFIX=$(CROSS_COMPILE) BOOTLOADER_OUT=../../../$(EMMC_BOOTLOADER_OUT) $(BOOTLOADER_PLATFORM) EMMC_BOOT=1 $(SIGNED_KERNEL) $(VERIFIED_BOOT) $(DEVICE_STATUS)
 
 # Keep build NAND & eMMC as default for targets still using TARGET_BOOTLOADER
 TARGET_BOOTLOADER := $(PRODUCT_OUT)/EMMCBOOT.MBN