Remove call-with-sigint

This comes from guile-knots now.

guix-data-service/utils.scm

@@ -52,8 +52,6 @@
 
             get-guix-metrics-updater
 
-            call-with-sigint
-
             spawn-port-monitoring-fiber
 
             make-queueing-channel))
@@ -187,18 +185,3 @@
                 (close-port sock)))
             #:timeout 20))
          #:unwind? #t)))))
-
-;; Copied from (fibers web server)
-(define (call-with-sigint thunk cvar)
-  (let ((handler #f))
-    (dynamic-wind
-      (lambda ()
-        (set! handler
-          (sigaction SIGINT (lambda (sig) (signal-condition! cvar)))))
-      thunk
-      (lambda ()
-        (if handler
-            ;; restore Scheme handler, SIG_IGN or SIG_DFL.
-            (sigaction SIGINT (car handler) (cdr handler))
-            ;; restore original C handler.
-            (sigaction SIGINT #f))))))