boot: zephyr: add Kconfig for arm cortex-m that implements a cache

The Cache is an optional configuration of both the ARM Cortex-M7 and
Cortex-M55. Previously, it was just checking that it was just an M7
rather than knowing that the CPU actually was built with the cache.

Signed-off-by: Ryan McClelland <ryanmcclelland@fb.com>
diff --git a/boot/zephyr/main.c b/boot/zephyr/main.c
index 5e20cb1..bac41a3 100644
--- a/boot/zephyr/main.c
+++ b/boot/zephyr/main.c
@@ -196,7 +196,7 @@
 #if CONFIG_MCUBOOT_CLEANUP_ARM_CORE
     cleanup_arm_nvic(); /* cleanup NVIC registers */
 
-#ifdef CONFIG_CPU_CORTEX_M7
+#ifdef CONFIG_CPU_CORTEX_M_HAS_CACHE
     /* Disable instruction cache and data cache before chain-load the application */
     SCB_DisableDCache();
     SCB_DisableICache();