kernel: Make system/vendor images depend on modules

* We're having a race with the kernel module build and vendor.img
  generation, and sometimes when vendor.img wins it won't include
  any modules in the image, which leads to all sorts of breakage

Change-Id: I2cdde96530aa8e47351cace76352788cde631058
diff --git a/build/tasks/kernel.mk b/build/tasks/kernel.mk
index 066ea1f..a8e49f7 100644
--- a/build/tasks/kernel.mk
+++ b/build/tasks/kernel.mk
@@ -168,6 +168,7 @@
 KERNEL_MODULES_OUT := $(TARGET_OUT)
 KERNEL_DEPMOD_STAGING_DIR := $(KERNEL_BUILD_OUT_PREFIX)$(call intermediates-dir-for,PACKAGING,depmod_system)
 KERNEL_MODULE_MOUNTPOINT := system
+$(INSTALLED_SYSTEMIMAGE_TARGET): $(TARGET_PREBUILT_INT_KERNEL)
 else ifeq ($(NEED_KERNEL_MODULE_VENDOR_OVERLAY),true)
 KERNEL_MODULES_OUT := $(TARGET_OUT_PRODUCT)/vendor_overlay/$(PRODUCT_TARGET_VNDK_VERSION)
 KERNEL_DEPMOD_STAGING_DIR := $(KERNEL_BUILD_OUT_PREFIX)$(call intermediates-dir-for,PACKAGING,depmod_product)
@@ -177,6 +178,7 @@
 KERNEL_MODULES_OUT := $(TARGET_OUT_VENDOR)
 KERNEL_DEPMOD_STAGING_DIR := $(KERNEL_BUILD_OUT_PREFIX)$(call intermediates-dir-for,PACKAGING,depmod_vendor)
 KERNEL_MODULE_MOUNTPOINT := vendor
+$(INSTALLED_VENDORIMAGE_TARGET): $(TARGET_PREBUILT_INT_KERNEL)
 endif
 MODULES_INTERMEDIATES := $(KERNEL_BUILD_OUT_PREFIX)$(call intermediates-dir-for,PACKAGING,kernel_modules)