soundwire: Fix incorrect return value check

pm_runtime_get_sync will return negative values for error
and 0 or 1 for success. Update the error check accordingly.
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 9d715fa0: ("soundwire: Add IO transfer")
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/soundwire/bus.c

@@ -305,7 +305,7 @@ int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 		return ret;
 
 	ret = pm_runtime_get_sync(slave->bus->dev);
-	if (!ret)
+	if (ret < 0)
 		return ret;
 
 	ret = sdw_transfer(slave->bus, &msg);
@@ -333,7 +333,7 @@ int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 		return ret;
 
 	ret = pm_runtime_get_sync(slave->bus->dev);
-	if (!ret)
+	if (ret < 0)
 		return ret;
 
 	ret = sdw_transfer(slave->bus, &msg);