rtems: Improve RTEMS_NO_RETURN attribute

Provide RTEMS_NO_RETURN also in case RTEMS_DEBUG is defined to prevent errors
like this:

error: no return statement in function returning non-void [-Werror=return-type]

Use C11 and C++11 standard means to declare a no-return function.

Close #4122.

bsps/include/bsp/bootcard.h

@@ -68,7 +68,7 @@ void bsp_reset(void);
  * This style of initialization ensures that the C++ global constructors are
  * executed after RTEMS is initialized.
  */
-void boot_card(const char *cmdline) RTEMS_NO_RETURN;
+RTEMS_NO_RETURN void boot_card(const char *cmdline);
 
 struct Per_CPU_Control;