be more iOS friendly when using TCP or TLS because the phone never sleeps thus drains the battery

src/mod/endpoints/mod_sofia/sofia.c

@@ -1477,8 +1477,6 @@ void *SWITCH_THREAD_FUNC sofia_profile_thread_run(switch_thread_t *thread, void
 									 TPTAG_TLS_VERIFY_POLICY(0)),
 							  TAG_IF(sofia_test_pflag(profile, PFLAG_TLS),
 									 TPTAG_TLS_VERSION(profile->tls_version)),
-							  TAG_IF(sofia_test_pflag(profile, PFLAG_TLS),
-									 TPTAG_KEEPALIVE(20000)),
 							  TAG_IF(!strchr(profile->sipip, ':'),
 									 NTATAG_UDP_MTU(65535)),
 							  TAG_IF(sofia_test_pflag(profile, PFLAG_DISABLE_SRV),