testsuites/jffs2: Add test for empty NOR FS

This adds a test to very that remounting a completely used, but empty
NOR JFFS2 filesystem is possible. Previously, this triggered an edge
condition in the JFFS2 scan code that prevented remount of a correctly
formed and uncorrupted filesystem.

spec/build/testsuites/fstests/fsjffs2empty01.yml

@@ -0,0 +1,21 @@
+SPDX-License-Identifier: CC-BY-SA-4.0 OR BSD-2-Clause
+build-type: test-program
+cflags: []
+copyrights:
+- Copyright (C) 2020 embedded brains GmbH & Co. KG
+cppflags: []
+cxxflags: []
+enabled-by: true
+features: c cprogram
+includes:
+- testsuites/fstests/jffs2_support
+ldflags: []
+links: []
+source:
+- testsuites/fstests/fsjffs2empty01/init.c
+stlib: []
+target: testsuites/fstests/fsjffs2empty01.exe
+type: build
+use-after: []
+use-before:
+- jffs2

spec/build/testsuites/fstests/grp.yml

@@ -51,6 +51,8 @@ links:
   uid: fsimfsconfig03
 - role: build-dependency
   uid: fsimfsgeneric01
+- role: build-dependency
+  uid: fsjffs2empty01
 - role: build-dependency
   uid: fsjffs2gc01
 - role: build-dependency