uORB::Publication improvements and cleanup (#14784)

- create common uORB::PublicationBase
 - uORB::PublicationQueued types are now type aliases
 - ORB_PRIO use enum type everywhere to avoid accidental misuse
 - PX4Accelerometer/PX4Gyroscope/etc driver libs explicitly advertise on construction, unadvertise on destruction. This is a workaround for any potential issues that might appear when accel/gyro cdev and uORB indexing doesn't align.

src/modules/uORB/uORB_tests/uORBTest_UnitTest.cpp

@@ -386,7 +386,7 @@ int uORBTest::UnitTest::test_multi()
 	}
 
 	/* test priorities */
-	int prio;
+	ORB_PRIO prio;
 
 	if (PX4_OK != orb_priority(sfd0, &prio)) {
 		return test_fail("prio #0");