[NET]: Terminology in ip-sysctl.txt

this minor patch fixes the description of net.ipv4.tcp_mem sysctl
in ip-sysctl.txt - the headline names the values "min, pressure, max",
while the description uses the "low, pressure, high" values.
Both tcp_rmem and tcp_wmem descriptions use the "min, pressure, max"
values, so I have changed the tcp_mem to match this and not vice versa.

Signed-off-by: Jan "Yenya" Kasprzak <kas@fi.muni.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/ip-sysctl.txt

@@ -294,15 +294,15 @@ tcp_rmem - vector of 3 INTEGERs: min, default, max
 	Default: 87380*2 bytes.
 
 tcp_mem - vector of 3 INTEGERs: min, pressure, max
-	low: below this number of pages TCP is not bothered about its
+	min: below this number of pages TCP is not bothered about its
 	memory appetite.
 
 	pressure: when amount of memory allocated by TCP exceeds this number
 	of pages, TCP moderates its memory consumption and enters memory
 	pressure mode, which is exited when memory consumption falls
-	under "low".
+	under "min".
 
-	high: number of pages allowed for queueing by all TCP sockets.
+	max: number of pages allowed for queueing by all TCP sockets.
 
 	Defaults are calculated at boot time from amount of available
 	memory.