core: Allow the board config to specify the kernel base address for mkbootimg

Signed-off-by: Dima Zavin <dima@android.com>
diff --git a/core/Makefile b/core/Makefile
index 9532ef2..18baa46 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -268,6 +268,11 @@
   INTERNAL_BOOTIMAGE_ARGS += --cmdline "$(BOARD_KERNEL_CMDLINE)"
 endif
 
+BOARD_KERNEL_BASE := $(strip $(BOARD_KERNEL_BASE))
+ifdef BOARD_KERNEL_BASE
+  INTERNAL_BOOTIMAGE_ARGS += --base $(BOARD_KERNEL_BASE)
+endif
+
 INSTALLED_BOOTIMAGE_TARGET := $(PRODUCT_OUT)/boot.img
 
 ifeq ($(TARGET_BOOTIMAGE_USE_EXT2),true)