MdeModulePkg Tcp4Dxe: Remove redundant functions

The functions that are never called have been removed.
They are SockRcvdErr,SockGroup and TcpPawsOK.
https://bugzilla.tianocore.org/show_bug.cgi?id=1062

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: shenglei <shenglei.zhang@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>

MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Option.h

@@ -126,20 +126,5 @@ TcpParseOption (
   IN OUT TCP_OPTION *Option
   );
 
-/**
-  Check the segment against PAWS.
-
-  @param  Tcb     Pointer to the TCP_CB of this TCP instance.
-  @param  TSVal   The timestamp value.
-
-  @retval 1       The segment passed the PAWS check.
-  @retval 0       The segment failed to pass the PAWS check.
-
-**/
-UINT32
-TcpPawsOK (
-  IN TCP_CB *Tcb,
-  IN UINT32 TSVal
-  );
 
 #endif