Fix copyright file

dependencies -> src/dependencies
mention sha256crypt being public domain

debian/copyright

@@ -6,11 +6,15 @@ Files: *
 Copyright: 2020 Raspberry Pi Ltd
 License: Apache-2.0
 
-Files: dependencies/mountutils/* dependencies/drivelist/*
+Files: src/dependencies/mountutils/* src/dependencies/drivelist/*
 Copyright: 2017 Balena.io 
 License: Apache-2.0
 
-Files-Excluded: dependencies/cmcurl/* dependencies/cmliblzma/* dependencies/fat32format/* dependencies/libarchive-3.4.1/* dependencies/zlib-1.2.11/*
+Files: src/dependencies/sha256crypt/*
+Copyright: Released into the Public Domain by Ulrich Drepper
+License: public-domain
+
+Files-Excluded: src/dependencies/cmcurl/* src/dependencies/cmliblzma/* src/dependencies/fat32format/* src/dependencies/libarchive-3.4.1/* src/dependencies/zlib-1.2.11/*
 Comment: Not used in Linux build (depending on the official packages instead) 
 
 License: Apache-2.0
@@ -29,3 +33,7 @@ License: Apache-2.0
  On Debian systems, the complete text of the Apache version 2.0 license
  can be found in "/usr/share/common-licenses/Apache-2.0".
 
+License: public-domain
+ SHA256-based Unix crypt implementation.
+ Released into the Public Domain by Ulrich Drepper
+

license.txt

@@ -30,7 +30,7 @@ This software depends on the following third-party components covered by open so
 - Balena.io mountutils (Apache license)
 - libarchive (new BSD license)
 - liblzma (public domain)
-- cryptsha256 (public domain)
+- sha256crypt (public domain)
 - zlib (zlib license)
 - libcurl (libcurl license)
 - fat32format.exe (GPL license)
@@ -1016,7 +1016,7 @@ liblzma license
 - liblzma is in the public domain.
 
 ==
-cryptsha256 license
+sha256crypt license
 ==
 
 SHA256-based Unix crypt implementation.