boot/boot_serial: Add boot_reset_request_hook to bs_reset

When hooks are enabled then boot_reset_request_hook will be
called to check whether it is allowed to reset a device.

Signed-off-by: Dominik Ermel <dominik.ermel@nordicsemi.no>

boot/boot_serial/src/boot_serial.c

@@ -657,8 +657,19 @@ out:
 static void
 bs_reset(char *buf, int len)
 {
-    bs_rc_rsp(0);
+    int rc = BOOT_HOOK_CALL(boot_reset_request_hook, 0, false);
+    if (rc == BOOT_RESET_REQUEST_HOOK_BUSY) {
+	rc = MGMT_ERR_EBUSY;
+    } else {
+        /* Currently whatever else is returned it is just converted
+         * to 0/no error. Boot serial starts accepting "force" parameter
+         * in command this needs to change.
+         */
+         rc = 0;
+    }
+    bs_rc_rsp(rc);
 
+    if (rc == 0) {
 #ifdef __ZEPHYR__
 #ifdef CONFIG_MULTITHREADING
         k_sleep(K_MSEC(250));
@@ -674,6 +685,7 @@ bs_reset(char *buf, int len)
         hal_system_reset();
 #endif
     }
+}
 
 /*
  * Parse incoming line of input from console.

boot/boot_serial/src/boot_serial_priv.h

@@ -41,6 +41,7 @@ extern "C" {
 #define MGMT_ERR_ENOMEM         2
 #define MGMT_ERR_EINVAL         3
 #define MGMT_ERR_ENOTSUP        8
+#define MGMT_ERR_EBUSY		10
 
 #define NMGR_OP_READ            0
 #define NMGR_OP_WRITE           2