tests: Use floating point task

These tests directly or indirectly use fprintf(), etc. which may use the
floating point unit.

Update #3076.

testsuites/samples/loopback/init.c

@@ -33,6 +33,7 @@ rtems_printer rtems_test_printer;
                                            RTEMS_NO_TIMESLICE | \
                                            RTEMS_NO_ASR | \
                                            RTEMS_INTERRUPT_LEVEL(0))
+#define CONFIGURE_INIT_TASK_ATTRIBUTES RTEMS_FLOATING_POINT
 
 #define CONFIGURE_INIT
 rtems_task Init(rtems_task_argument argument);