kernel: Remove deprecated flag errors

* All devices should have migrated by now

Change-Id: Iecef58a1193b87ecb084eccda27a3b4e89f42219
diff --git a/build/tasks/kernel.mk b/build/tasks/kernel.mk
index b42d86d..61d63bc 100644
--- a/build/tasks/kernel.mk
+++ b/build/tasks/kernel.mk
@@ -77,12 +77,6 @@
 ifeq ($(BOARD_KERNEL_IMAGE_NAME),)
 $(error BOARD_KERNEL_IMAGE_NAME not defined.)
 endif
-ifneq ($(TARGET_USES_UNCOMPRESSED_KERNEL),)
-$(error TARGET_USES_UNCOMPRESSED_KERNEL is deprecated.)
-endif
-ifneq ($(TARGET_KERNEL_APPEND_DTB),)
-$(error TARGET_KERNEL_APPEND_DTB is deprecated.)
-endif
 TARGET_PREBUILT_INT_KERNEL := $(KERNEL_OUT)/arch/$(KERNEL_ARCH)/boot/$(BOARD_KERNEL_IMAGE_NAME)
 
 ifneq ($(TARGET_KERNEL_ADDITIONAL_CONFIG),)