Fix two typos in zip_file_add documentation.
Noted by Norbert de Jonge.
diff --git a/man/zip_file_add.mdoc b/man/zip_file_add.mdoc
index 5600cc3..bef7081 100644
--- a/man/zip_file_add.mdoc
+++ b/man/zip_file_add.mdoc
@@ -111,9 +111,9 @@
.Sh EXAMPLES
.Bd -literal -offset indent
zip_source_t *s;
-const char buf="teststring";
+const char *buf="teststring";
-if ((s=zip_source_buffer(archive, buffer, sizeof(buf), 0)) == NULL ||
+if ((s=zip_source_buffer(archive, buf, sizeof(buf), 0)) == NULL ||
zip_file_add(archive, name, s, ZIP_FL_ENC_UTF_8) \*[Lt] 0) {
zip_source_free(s);
printf("error adding file: %s\en", zip_strerror(archive));