gnu: sequoia4pEp: Move to sequoia.scm.

Don't have cross module package inheritance.

* gnu/packages/pep.scm (sequoia4pEp): Move to ...
* gnu/packages/sequoia.scm (sequoia4pEp): ... here. Hide package.

gnu/packages/pep.scm

@@ -81,21 +81,6 @@ shell provides options to redirect the output into a pipe or a file.")
        (file-name (string-append name "-" version))
        (sha256 (base32 checksum)))))))
 
-(define sequoia4pEp
-  ;; Currently pEp Engine requires sequoia in not-so-current version
-  (package/inherit sequoia
-    (name "sequoia")
-    (version "0.15.0-pEp")
-    (source
-     (origin
-       (method git-fetch)
-       (uri (git-reference
-             (url "https://gitlab.com/sequoia-pgp/sequoia.git")
-             (commit "0eb1b6cd846ea8c36b3dfdf01ec88383fc64f2fe")))
-       (sha256
-        (base32 "06dqs9whwp9lfibwp8dqm0aw4nm3s3v4jp2n4fz51zcvsld40nfh"))
-       (file-name (git-file-name name version))))))
-
 (define-public pep-engine
   (package
     (name "pep-engine")

gnu/packages/sequoia.scm

@@ -203,3 +203,19 @@
 several crates, providing both a low-level and a high-level API for dealing
 with OpenPGP data.")
     (license license:gpl2+)))
+
+(define-public sequoia4pEp
+  ;; Currently pEp Engine requires sequoia in not-so-current version
+  (package/inherit sequoia
+    (name "sequoia")
+    (version "0.15.0-pEp")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://gitlab.com/sequoia-pgp/sequoia.git")
+             (commit "0eb1b6cd846ea8c36b3dfdf01ec88383fc64f2fe")))
+       (sha256
+        (base32 "06dqs9whwp9lfibwp8dqm0aw4nm3s3v4jp2n4fz51zcvsld40nfh"))
+       (file-name (git-file-name name version))))
+    (properties `((hidden? . #t)))))