instance.c: Fix a compiler warning.

  ../instance.c: In function ‘srd_inst_find_by_id’:
  ../instance.c:485:3: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
     if (di = srd_inst_find_by_id_stack(inst_id, tmp))
     ^~

1 files changed, 1 insertions, 1 deletions

diff --git a/instance.c b/instance.c
index 5b98336..00bc802 100644
--- a/instance.c
+++ b/instance.c
@@ -482,7 +482,7 @@ SRD_API struct srd_decoder_inst *srd_inst_find_by_id(struct srd_session *sess,
 	di = NULL;
 	for (l = sess->di_list; l; l = l->next) {
 		tmp = l->data;
-		if (di = srd_inst_find_by_id_stack(inst_id, tmp))
+		if ((di = srd_inst_find_by_id_stack(inst_id, tmp)) != NULL)
 			break;
 	}