Bluetooth: Use correct type for userspace exported structs

It should be __u8 instead of u8.

Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
index 61953dc..ffc1377 100644
--- a/include/net/bluetooth/mgmt.h
+++ b/include/net/bluetooth/mgmt.h
@@ -163,9 +163,9 @@
 
 struct mgmt_link_key_info {
 	struct mgmt_addr_info addr;
-	u8	type;
-	u8	val[16];
-	u8	pin_len;
+	__u8	type;
+	__u8	val[16];
+	__u8	pin_len;
 } __packed;
 
 #define MGMT_OP_LOAD_LINK_KEYS		0x0012