boot/zephyr: add option to relocate interrupts to application

If CONFIG_BOOT_INTR_VEC_RELOC is set, the mcuboot will
relocate the interrupt vector to the booted application.

Signed-off-by: Rafał Kuźnia <rafal.kuznia@nordicsemi.no>
diff --git a/boot/zephyr/Kconfig b/boot/zephyr/Kconfig
index e2af99e..10cd885 100644
--- a/boot/zephyr/Kconfig
+++ b/boot/zephyr/Kconfig
@@ -388,6 +388,15 @@
 
 endif # MCUBOOT_SERIAL
 
+config BOOT_INTR_VEC_RELOC
+	bool "Relocate the interrupt vector to the application"
+	default n
+	depends on SW_VECTOR_RELAY || CPU_CORTEX_M_HAS_VTOR
+	help
+	  Relocate the interrupt vector to the application before it is started.
+	  Select this option if application requires vector relocation,
+	  but it doesn't relocate vector in its reset handler.
+
 config UPDATEABLE_IMAGE_NUMBER
 	int "Number of updateable images"
 	default 1