Fix 0c4 on failed socket open when socket close attempted

[1000TurquoisePogs]

Testing within zowe/zowe-install-packaging#4447 revealed some limitations. This PR fixes a bug in which socketClose was attempted when there was no socket to close - the call has now been moved to the other side of the conditional in which the server socket exists.

[MarkAckert]

The S0C4 moved to successful binds:

_BPX_JOBNAME=WHOSV ./bind-test --host 0.0.0.0 --port 10442
Bind succeeded (pointer=0x1B100098, rc=0x0, rsn=0x0)
CEE3204S The system detected a protection exception (System Completion Code=0C4).
         From compile unit ZZOW11:../../deps/zowe-common-c/c/bpxskt.c/ at entry point socketClose at statement 1674 at compile unit offset +000000001A70C594 at entry offset +000000000000004C at address 000000001A70C594.
SIGSEGV

It seems like the bind-util can't detect ports in use when the host parameter is different than the running application. For example, z/OSMF is running on 10443 below using the system host, and this returns bind success:

_BPX_JOBNAME=WHOSV ./bind-test --host 127.0.0.1 --port 10443
Resolved IP address as 127.0.0.1
Bind succeeded (pointer=0x1B0FD098, rc=0x0, rsn=0x0)
CEE3204S The system detected a protection exception (System Completion Code=0C4).

Similar to above, bind-util can detect a running Zowe instance, but only when using 0.0.0.0, not loopback:

_BPX_JOBNAME=WHOSV ./bind-test --host 127.0.0.1 --port 7554
Resolved IP address as 127.0.0.1
Bind succeeded (pointer=0x1B0FD098, rc=0x0, rsn=0x0)
CEE3204S The system detected a protection exception (System Completion Code=0C4).

_BPX_JOBNAME=WHOSV ./bind-test --host 0.0.0.0 --port 7554
Error: Bind failed (rc=0x45b, rsn=0x744c7247)
Error: Port 7554 was already occupied

[Martin-Zeithaml]

See https://github.com/zowe/zss/pull/793/files#r2272627830

[Martin-Zeithaml]

This was previously abending, now working fine:

/zss/bin: _BPX_JOBNAME=ZWESLSTC ./bind-test --host 10.20.30.40 --port 7556
Resolved IP address as 10.20.30.40
Bind succeeded (pointer=0x3B08D098, rc=0x0, rsn=0x0)