fsi: gpio: Trace busy count

An observation from trace output of the existing FSI tracepoints was
that the remote device was sometimes reporting as busy. Add a new
tracepoint reporting the busy count in order to get a better grip on how
often this is the case.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Eddie James <eajames@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Joel Stanley <joel@jms.id.au>

drivers/fsi/fsi-master-gpio.c

@@ -401,6 +401,9 @@ retry:
 		break;
 	}
 
+	if (busy_count > 0)
+		trace_fsi_master_gpio_poll_response_busy(master, busy_count);
+
 	/* Clock the slave enough to be ready for next operation */
 	clock_zeros(master, FSI_GPIO_PRIME_SLAVE_CLOCKS);
 	return rc;