IO driver: Reduce perf counters

src/drivers/px4io/px4io.cpp

@@ -900,7 +900,7 @@ PX4IO::init()
 	_task = px4_task_spawn_cmd("px4io",
 				   SCHED_DEFAULT,
 				   SCHED_PRIORITY_ACTUATOR_OUTPUTS,
-				   1500,
+				   1400,
 				   (main_t)&PX4IO::task_main_trampoline,
 				   nullptr);
 

src/drivers/px4io/px4io_serial.cpp

@@ -180,7 +180,8 @@ PX4IO_serial::PX4IO_serial() :
 	_rx_dma_status(_dma_status_inactive),
 	_bus_semaphore(SEM_INITIALIZER(0)),
 	_completion_semaphore(SEM_INITIALIZER(0)),
-	_pc_txns(perf_alloc(PC_ELAPSED, "io_txns     ")),
+	_pc_txns(perf_alloc(PC_ELAPSED, "io_txns")),
+#if 0
 	_pc_dmasetup(perf_alloc(PC_ELAPSED,	"io_dmasetup ")),
 	_pc_retries(perf_alloc(PC_COUNT,	"io_retries  ")),
 	_pc_timeouts(perf_alloc(PC_COUNT,	"io_timeouts ")),
@@ -190,6 +191,17 @@ PX4IO_serial::PX4IO_serial() :
 	_pc_uerrs(perf_alloc(PC_COUNT,		"io_uarterrs ")),
 	_pc_idle(perf_alloc(PC_COUNT,		"io_idle     ")),
 	_pc_badidle(perf_alloc(PC_COUNT,	"io_badidle  "))
+#else
+	_pc_dmasetup(nullptr),
+	_pc_retries(nullptr),
+	_pc_timeouts(nullptr),
+	_pc_crcerrs(nullptr),
+	_pc_dmaerrs(nullptr),
+	_pc_protoerrs(nullptr),
+	_pc_uerrs(nullptr),
+	_pc_idle(nullptr),
+	_pc_badidle(nullptr)
+#endif
 {
 	g_interface = this;
 }