makefile: Fix dependencies for privileged stacks

This patch fixes the dependency chain for priviliged stack
generation.  This fixes a problem when compiling after making
significant changes that would shift the privileged stack area.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 61c49f3..52430a9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -709,7 +709,7 @@
     ${GPERF} -C
     --output-file ${PRIV_STACKS_OUTPUT_SRC_PRE}
     ${PRIV_STACKS}
-    DEPENDS priv_stacks
+    DEPENDS priv_stacks ${PRIV_STACKS}
     WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
     )
   add_custom_target(priv_stacks_output_src_pre DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/${PRIV_STACKS_OUTPUT_SRC_PRE})
@@ -727,7 +727,7 @@
     -o ${PRIV_STACKS_OUTPUT_SRC}
     -p "struct _k_priv_stack_map"
     $<$<BOOL:${CMAKE_VERBOSE_MAKEFILE}>:--verbose>
-    DEPENDS priv_stacks_output_src_pre
+    DEPENDS priv_stacks_output_src_pre ${PRIV_STACKS_OUTPUT_SRC_PRE}
     WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
     )
   add_custom_target(priv_stacks_output_src DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/${PRIV_STACKS_OUTPUT_SRC})