iio: imu/mpu6050: support dual-edge IRQ

Make mpu6050 usable on platforms which provide only any-edge interrupts.
One example of this kind of platform is AT91SAM9G45
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/imu/inv_mpu6050/inv_mpu_core.c

@@ -1220,7 +1220,7 @@ int inv_mpu_core_probe(struct regmap *regmap, int irq, const char *name,
 	irq_type = irqd_get_trigger_type(desc);
 	if (!irq_type)
 		irq_type = IRQF_TRIGGER_RISING;
-	if (irq_type == IRQF_TRIGGER_RISING)
+	if (irq_type & IRQF_TRIGGER_RISING)	// rising or both-edge
 		st->irq_mask = INV_MPU6050_ACTIVE_HIGH;
 	else if (irq_type == IRQF_TRIGGER_FALLING)
 		st->irq_mask = INV_MPU6050_ACTIVE_LOW;

drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c

@@ -185,11 +185,8 @@ irqreturn_t inv_mpu6050_read_fifo(int irq, void *p)
 			"failed to ack interrupt\n");
 		goto flush_fifo;
 	}
-	if (!(int_status & INV_MPU6050_BIT_RAW_DATA_RDY_INT)) {
-		dev_warn(regmap_get_device(st->map),
-			"spurious interrupt with status 0x%x\n", int_status);
+	if (!(int_status & INV_MPU6050_BIT_RAW_DATA_RDY_INT))
 		goto end_session;
-	}
 
 	if (!(st->chip_config.accl_fifo_enable |
 		st->chip_config.gyro_fifo_enable |