[nrf fromtree] boot: zephyr: Only call sys_clock_disable when supported

Only call sys_clock_disable when the system clock driver support
this feature.

Signed-off-by: Joakim Andersson <[email protected]>
Signed-off-by: Dominik Ermel <[email protected]>
(cherry picked from commit 6242c86)

Author: joerchan

boot/zephyr/main.c

@@ -207,7 +207,9 @@ static void do_boot(struct boot_rsp *rsp)
                                      rsp->br_hdr->ih_hdr_size);
 #endif
 
-    sys_clock_disable();
+    if (IS_ENABLED(CONFIG_SYSTEM_TIMER_HAS_DISABLE_SUPPORT)) {
+        sys_clock_disable();
+    }
 
 #ifdef CONFIG_USB_DEVICE_STACK
     /* Disable the USB to prevent it from firing interrupts */