fix inefficient choice of tlsdesc function due to off-by-one

tls_id is one-based, whereas [static_]tls_cnt is a count, so
comparison for checking that a given tls_id is dynamic rather than
static needs to use strict inequality.
diff --git a/ldso/dynlink.c b/ldso/dynlink.c
index 41534e9..8242a1d 100644
--- a/ldso/dynlink.c
+++ b/ldso/dynlink.c
@@ -438,7 +438,7 @@
 #endif
 		case REL_TLSDESC:
 			if (stride<3) addend = reloc_addr[1];
-			if (runtime && def.dso->tls_id >= static_tls_cnt) {
+			if (runtime && def.dso->tls_id > static_tls_cnt) {
 				struct td_index *new = malloc(sizeof *new);
 				if (!new) {
 					error(