net: rename busy poll socket op and globals

Rename LL_SO to BUSY_POLL_SO
Rename sysctl_net_ll_{read,poll} to sysctl_busy_{read,poll}
Fix up users of these variables.
Fix documentation for sysctl.

a patch for the socket.7  man page will follow separately,
because of limitations of my mail setup.

Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/sock.c b/net/core/sock.c
index 9bfe83f4..548d716 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -901,7 +901,7 @@
 		break;
 
 #ifdef CONFIG_NET_LL_RX_POLL
-	case SO_LL:
+	case SO_BUSY_POLL:
 		/* allow unprivileged users to decrease the value */
 		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
 			ret = -EPERM;
@@ -1171,7 +1171,7 @@
 		break;
 
 #ifdef CONFIG_NET_LL_RX_POLL
-	case SO_LL:
+	case SO_BUSY_POLL:
 		v.val = sk->sk_ll_usec;
 		break;
 #endif
@@ -2294,7 +2294,7 @@
 
 #ifdef CONFIG_NET_LL_RX_POLL
 	sk->sk_napi_id		=	0;
-	sk->sk_ll_usec		=	sysctl_net_ll_read;
+	sk->sk_ll_usec		=	sysctl_net_busy_read;
 #endif
 
 	/*