add .gitignore for src directory
diff --git a/src/.gitignore b/src/.gitignore
new file mode 100644
index 0000000..7cf2e0a
--- /dev/null
+++ b/src/.gitignore
@@ -0,0 +1,4 @@
+hnbap_decoder.c
+hnbap_encoder.c
+hnbap_ies_defs.h
+hnbgw