[IOT-2146] Fixed Thread-unsafe code in tcp adapter

[IOT-2146] Fixed Thread-unsafe code in tcp adapter

- Remove potential thread safety bugs in catcpserver

Change-Id: I95dba029b47e2a14b3217565a401c631b0b84cc2
Signed-off-by: hyuna0213.jo <hyuna0213.jo@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/19767
Tested-by: jenkins-iotivity <jenkins@iotivity.org>
Reviewed-by: Uze Choi <uzchoi@samsung.com>
Reviewed-by: koushik girijala <g.koushik@samsung.com>
Reviewed-by: Jaehong Jo <jaehong.jo@samsung.com>
Reviewed-by: Dan Mihai <Daniel.Mihai@microsoft.com>
Reviewed-by: Ashok Babu Channa <ashok.channa@samsung.com>