gnu: Remove rust-chalk-solve-0.75.

* gnu/packages/crates-io.scm (rust-chalk-solve-0.75): Delete variable.

Change-Id: I351b4f120b9fb6c9e089265a45ca27feabcd8364

gnu/packages/crates-io.scm

@@ -11925,40 +11925,6 @@ macros.")
 clauses.")
     (license (list license:asl2.0 license:expat))))
 
-(define-public rust-chalk-solve-0.75
-  (package
-    (name "rust-chalk-solve")
-    (version "0.75.0")
-    (source
-     (origin
-       (method url-fetch)
-       (uri (crate-uri "chalk-solve" version))
-       (file-name
-        (string-append name "-" version ".tar.gz"))
-       (sha256
-        (base32
-         "07gaf59zr7pgpr01l3si7a8iici2qh5dh2w2b05agaq5cvds3lm5"))))
-    (build-system cargo-build-system)
-    (arguments
-     `(#:skip-build? #t
-       #:cargo-inputs
-       (("rust-chalk-derive" ,rust-chalk-derive-0.75)
-        ("rust-chalk-ir" ,rust-chalk-ir-0.75)
-        ("rust-ena" ,rust-ena-0.14)
-        ("rust-itertools" ,rust-itertools-0.10)
-        ("rust-petgraph" ,rust-petgraph-0.5)
-        ("rust-rustc-hash" ,rust-rustc-hash-1)
-        ("rust-tracing" ,rust-tracing-0.1)
-        ("rust-tracing-subscriber"
-         ,rust-tracing-subscriber-0.3)
-        ("rust-tracing-tree" ,rust-tracing-tree-0.2))))
-    (home-page "https://github.com/rust-lang/chalk")
-    (synopsis
-     "Combines the chalk-engine with chalk-ir")
-    (description
-     "This package provides a combines the chalk-engine with chalk-ir.")
-    (license (list license:asl2.0 license:expat))))
-
 (define-public rust-chan-0.1
   (package
     (name "rust-chan")