libtests/dl10: Enter shell on demand

Use rtems_shell_wait_for_input() similar to other potentially
interactive test programs.

testsuites/libtests/dl10/init.c

@@ -27,9 +27,6 @@
 
 const char rtems_test_name[] = "libdl (RTL) 10";
 
-/* forward declarations to avoid warnings */
-static rtems_task Init(rtems_task_argument argument);
-
 #include "dl10-tar.h"
 
 #define TARFILE_START dl10_tar
@@ -46,9 +43,18 @@ static int test(void)
   return 0;
 }
 
+static void notification(int fd, int seconds_remaining, void *arg)
+{
+  printf(
+    "Press any key to enter shell (%is remaining)\n",
+    seconds_remaining
+  );
+}
+
 static void Init(rtems_task_argument arg)
 {
   int e;
+  rtems_status_code sc;
 
   TEST_BEGIN();
 
@@ -76,6 +82,12 @@ static void Init(rtems_task_argument arg)
     exit (1);
   }
 
+
+  sc = rtems_shell_wait_for_input (STDIN_FILENO,
+                                   20,
+                                   notification,
+                                   NULL);
+  if (sc == RTEMS_SUCCESSFUL) {
     rtems_shell_init ("SHLL",
                       RTEMS_MINIMUM_STACK_SIZE * 4,
                       100,
@@ -83,6 +95,7 @@ static void Init(rtems_task_argument arg)
                       false,
                       true,
                       NULL);
+  }
 
   TEST_END();