NFC: llcp: Implement socket options

Some LLCP services (e.g. the validation ones) require some control over
the LLCP link parameters like the receive window (RW) or the MIU extension
(MIUX). This can only be done through socket options.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/include/linux/socket.h b/include/linux/socket.h
index 2b9f74b..428c37a 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -298,6 +298,7 @@
 #define SOL_IUCV	277
 #define SOL_CAIF	278
 #define SOL_ALG		279
+#define SOL_NFC		280
 
 /* IPX options */
 #define IPX_TYPE	1