gnu: Remove rust-rowan-0.15.

* gnu/packages/crates-io.scm (rust-rowan-0.15): Delete variable.

Change-Id: Ia3194f04a4adf8598311b2ad504bcb48203e5b3c

gnu/packages/crates-io.scm

@@ -65108,37 +65108,6 @@ text-buffer for applications such as text editors.  Ropey is fast, robust, and
 can handle huge texts and memory-incoherent edits with ease.")
     (license license:expat)))
 
-(define-public rust-rowan-0.15
-  (package
-    (name "rust-rowan")
-    (version "0.15.2")
-    (source
-     (origin
-       (method url-fetch)
-       (uri (crate-uri "rowan" version))
-       (file-name
-        (string-append name "-" version ".tar.gz"))
-       (sha256
-        (base32
-         "1ilxrar5npwnsb575gxh2gp8hi3032mm20sapzw72sv58gn8zski"))))
-    (build-system cargo-build-system)
-    (arguments
-     `(#:skip-build? #t
-       #:cargo-inputs
-       (("rust-countme" ,rust-countme-3)
-        ("rust-hashbrown" ,rust-hashbrown-0.11)
-        ("rust-memoffset" ,rust-memoffset-0.6)
-        ("rust-rustc-hash" ,rust-rustc-hash-1)
-        ("rust-serde" ,rust-serde-1)
-        ("rust-text-size" ,rust-text-size-1))
-       #:cargo-development-inputs
-       (("rust-m-lexer" ,rust-m-lexer-0.0.4))))
-    (home-page "https://github.com/rust-analyzer/rowan")
-    (synopsis "Library for generic lossless syntax trees")
-    (description
-     "This package provides a library for generic lossless syntax trees.")
-    (license (list license:expat license:asl2.0))))
-
 (define-public rust-roxmltree-0.20
   (package
     (name "rust-roxmltree")