slurmrestd - Demote send_http_connection_close() to static

Demote send_http_connection_close() to _send_http_connection_close() as
external linkage is not required.

Issue: 50189
diff --git a/src/slurmrestd/http.c b/src/slurmrestd/http.c
index 6dc7240..6083834 100644
--- a/src/slurmrestd/http.c
+++ b/src/slurmrestd/http.c
@@ -480,7 +480,13 @@
 	return xstrdup_printf("%s: %zu" CRLF, name, value);
 }
 
-extern int send_http_connection_close(http_context_t *ctxt)
+/*
+ * Send HTTP close notification header
+ *	Warns the client that we are about to close the connection.
+ * IN ctxt - connection context
+ * RET SLURM_SUCCESS or error
+ */
+static int _send_http_connection_close(http_context_t *ctxt)
 {
 	return _write_fmt_header(ctxt->con, "Connection", "Close");
 }
@@ -608,7 +614,7 @@
 	if (request->connection_close ||
 	    _valid_http_version(request->http_version.major,
 				request->http_version.minor))
-		send_http_connection_close(context);
+		_send_http_connection_close(context);
 
 	/* ensure connection gets closed */
 	conmgr_con_queue_close_free(&context->ref);
@@ -684,7 +690,7 @@
 	if (request->connection_close) {
 		/* Notify client that this connection will be closed now */
 		if (request->connection_close)
-			send_http_connection_close(context);
+			_send_http_connection_close(context);
 
 		conmgr_con_queue_close_free(&context->ref);
 		context->con = NULL;
diff --git a/src/slurmrestd/http.h b/src/slurmrestd/http.h
index bf10c8d..c08b371 100644
--- a/src/slurmrestd/http.h
+++ b/src/slurmrestd/http.h
@@ -120,14 +120,6 @@
 } send_http_response_args_t;
 
 /*
- * Send HTTP close notification.
- * 	Warns the client that we are about to close the connection.
- * IN args arguments of response
- * RET SLURM_SUCCESS or error
- */
-extern int send_http_connection_close(http_context_t *ctxt);
-
-/*
  * Send HTTP response
  * IN args arguments of response
  * RET SLURM_SUCCESS or error