BUG/CLEANUP: CLI: report the proper field states in "show sess"

Commit 16f649c ("REORG: polling: rename "fd_spec" to "fd_cache"")
missed the server-facing connection during the rename, so the old
names are still in used and add a bit of confusion during the
debugging.

This should be backported to 1.6 and 1.5.
diff --git a/src/dumpstats.c b/src/dumpstats.c
index 2cfaded..cc38038 100644
--- a/src/dumpstats.c
+++ b/src/dumpstats.c
@@ -5591,7 +5591,7 @@
 			              obj_base_ptr(conn->target));
 
 			chunk_appendf(&trash,
-			              "      flags=0x%08x fd=%d fd_spec_e=%02x fd_spec_p=%d updt=%d\n",
+			              "      flags=0x%08x fd=%d fd.state=%02x fd.cache=%d updt=%d\n",
 			              conn->flags,
 			              conn->t.sock.fd,
 			              conn->t.sock.fd >= 0 ? fdtab[conn->t.sock.fd].state : 0,