kernel: Move full kernel build guard flag below all targets

* The Pixel DTBO generation step should also be guarded by the full
  kernel build flag.

Change-Id: I06d230b1b32ad9d974f90bfe6ae82008f4454d83
diff --git a/build/tasks/kernel.mk b/build/tasks/kernel.mk
index 54812a9..6dd06b5 100644
--- a/build/tasks/kernel.mk
+++ b/build/tasks/kernel.mk
@@ -266,8 +266,6 @@
 	env KCONFIG_NOTIMESTAMP=true \
 		 $(PATH_OVERRIDE) $(MAKE) -C $(KERNEL_SRC) O=$(KERNEL_OUT) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) $(KERNEL_CLANG_TRIPLE) $(KERNEL_CC) alldefconfig
 
-endif # FULL_KERNEL_BUILD
-
 TARGET_PREBUILT_DTBO = $(PRODUCT_OUT)/dtbo/arch/$(KERNEL_ARCH)/boot/dtbo.img
 $(TARGET_PREBUILT_DTBO): $(AVBTOOL)
 	echo -e ${CL_GRN}"Building DTBO.img"${CL_RST}
@@ -279,6 +277,8 @@
 		--partition_name dtbo $(INTERNAL_AVB_DTBO_SIGNING_ARGS) \
 		$(BOARD_AVB_DTBO_ADD_HASH_FOOTER_ARGS)
 
+endif # FULL_KERNEL_BUILD
+
 ## Install it
 
 ifeq ($(NEEDS_KERNEL_COPY),true)