gnu: Remove rust-process-control-3.

* gnu/packages/crates-io.scm (rust-process-control-3): Delete variable.

gnu/packages/crates-io.scm

@@ -44402,31 +44402,6 @@ (define-public rust-procedural-masquerade-0.1
 @code{proc_macro_derive} pretend to be @code{proc_macro}.")
     (license (list license:expat license:asl2.0))))
 
-(define-public rust-process-control-3
-  (package
-    (name "rust-process-control")
-    (version "3.1.0")
-    (source
-     (origin
-       (method url-fetch)
-       (uri (crate-uri "process_control" version))
-       (file-name (string-append name "-" version ".tar.gz"))
-       (sha256
-        (base32 "1v5j6ajr3fprpay8754874rmi622a1vk5rld88p1jk04wha413pm"))))
-    (build-system cargo-build-system)
-    (arguments
-     `(#:skip-build? #t
-       #:cargo-inputs
-       (("rust-crossbeam-channel" ,rust-crossbeam-channel-0.5)
-        ("rust-libc" ,rust-libc-0.2)
-        ("rust-winapi" ,rust-winapi-0.3))))
-    (home-page "https://github.com/dylni/process_control")
-    (synopsis "Methods for ergonomically running processes with timeouts")
-    (description
-     "This crate allows running a process with a timeout, with the option to
-terminate it automatically afterward.")
-    (license (list license:expat license:asl2.0))))
-
 (define-public rust-progress-0.2
   (package
     (name "rust-progress")