CLEANUP: global: remove the nbproc field from the global structure

Let's use 1 in the rare places where it was still referenced since it's
now its only possible value.
diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index 6839132..059fef3 100644
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -4979,8 +4979,7 @@
 	if (!ssl_shctx && global.tune.sslcachesize) {
 		alloc_ctx = shctx_init(&ssl_shctx, global.tune.sslcachesize,
 		                       sizeof(struct sh_ssl_sess_hdr) + SHSESS_BLOCK_MIN_SIZE, -1,
-		                       sizeof(*sh_ssl_sess_tree),
-		                       ((global.nbthread > 1) || (!global_ssl.private_cache && (global.nbproc > 1))) ? 1 : 0);
+		                       sizeof(*sh_ssl_sess_tree), (global.nbthread > 1));
 		if (alloc_ctx <= 0) {
 			if (alloc_ctx == SHCTX_E_INIT_LOCK)
 				ha_alert("Unable to initialize the lock for the shared SSL session cache. You can retry using the global statement 'tune.ssl.force-private-cache' but it could increase CPU usage due to renegotiations if nbproc > 1.\n");