net: doc: merge /proc/sys/net/core/* documents into one place

All parameter descriptions in /proc/sys/net/core/* now is separated
two places. So, merge them into Documentation/sysctl/net.txt.

Signed-off-by: Shan Wei <davidshan@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/ip-sysctl.txt

@@ -1484,11 +1484,8 @@ addr_scope_policy - INTEGER
 
 
 /proc/sys/net/core/*
-dev_weight - INTEGER
-	The maximum number of packets that kernel can handle on a NAPI
-	interrupt, it's a Per-CPU variable.
+	Please see: Documentation/sysctl/net.txt for descriptions of these entries.
 
-	Default: 64
 
 /proc/sys/net/unix/*
 max_dgram_qlen - INTEGER

Documentation/sysctl/net.txt

@@ -43,6 +43,13 @@ Values :
 	1 - enable the JIT
 	2 - enable the JIT and ask the compiler to emit traces on kernel log.
 
+dev_weight
+--------------
+
+The maximum number of packets that kernel can handle on a NAPI interrupt,
+it's a Per-CPU variable.
+Default: 64
+
 rmem_default
 ------------