There may be a memory leak in main in /src/tools/sceac-example.c

When failed to access reader, cxt needs to be released before
exiting the program. Like in the patch of CVE-2019-6502, a
sc_release_context(ctx) is needed before line 71, or a
memory leak may occur.

src/tools/sceac-example.c

@@ -68,6 +68,7 @@ main (int argc, char **argv)
 	reader = sc_ctx_get_reader(ctx, 0);
 	if (!reader) {
 		fprintf(stderr, "Failed to access reader 0");
+		sc_release_context(ctx);
 		exit(1);
 	}