Don't bail out if Discovery is in progress when getting the rfcomm channel.

We should be having the SDP record in the cache. In the very rare
case, that the remote device's SDP records have changed and if a discovery
is in progress, we would have already updated the cache or if we have not
queried the device yet, we are going to fail anyways.
diff --git a/src/device.c b/src/device.c
index a3db57d..0d7a667 100644
--- a/src/device.c
+++ b/src/device.c
@@ -808,9 +808,6 @@
 	uint16_t attrId;
 	int err;
 
-	if (device->browse)
-		return g_dbus_create_error(msg, ERROR_INTERFACE ".InProgress",
-						"Discover in progress");
 	if (dbus_message_get_args(msg, NULL, DBUS_TYPE_STRING, &pattern,
 					DBUS_TYPE_UINT16, &attrId,
 					DBUS_TYPE_INVALID) == FALSE)