tasks: kernel: Clarify prebuilt kernel deprecation notice

Change-Id: I229029a3b36c5564a445752c6e495817a0969240
diff --git a/build/tasks/kernel.mk b/build/tasks/kernel.mk
index b5690d0..92f5187 100644
--- a/build/tasks/kernel.mk
+++ b/build/tasks/kernel.mk
@@ -110,7 +110,7 @@
     ifneq ($(HAS_PREBUILT_KERNEL),)
         $(warning ***************************************************************)
         $(warning * Using prebuilt kernel binary instead of source              *)
-        $(warning * THIS IS DEPRECATED, AND WILL BE DISCONTINUED                *)
+        $(warning * THIS IS DEPRECATED, AND IS NOT ADVISED.                     *)
         $(warning * Please configure your device to download the kernel         *)
         $(warning * source repository to $(KERNEL_SRC))
         $(warning * for more information                                        *)