Revert "boot: zephyr: Disable HW stack protection"

This reverts commit 4dc12f4807099f0c210cad350e1439971677b9c0.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
diff --git a/boot/zephyr/prj.conf b/boot/zephyr/prj.conf
index f114c04..7f15372 100644
--- a/boot/zephyr/prj.conf
+++ b/boot/zephyr/prj.conf
@@ -33,5 +33,3 @@
 CONFIG_LOG=y
 ### Ensure Zephyr logging changes don't use more resources
 CONFIG_LOG_DEFAULT_LEVEL=0
-
-CONFIG_HW_STACK_PROTECTION=n