build: marionette: Make it possible to reboot VM during tests.

* gnu/build/marionette.scm (make-marionette): Add 'reconnect=1' socket
parameter.
* gnu/system/vm.scm (common-qemu-options): Remove '-no-reboot' option.

Change-Id: I5e100543ddddba0aea3ebe4e2f5cb8b0261c0d73

gnu/build/marionette.scm

@@ -108,7 +108,7 @@ QEMU monitor and to the guest's backdoor REPL."
     (list "-nographic"
           "-monitor" (string-append "unix:" socket-directory "/monitor")
           "-chardev" (string-append "socket,id=repl,path=" socket-directory
-                                    "/repl")
+                                    "/repl,reconnect=1")
           "-chardev" (string-append "socket,id=qga,server=on,wait=off,path="
                                     socket-directory "/qemu-ga")
 

gnu/system/vm.scm

@@ -227,7 +227,6 @@ with '-virtfs' options for the host file systems listed in SHARED-FS."
             '("-enable-kvm")
             '())
 
-     "-no-reboot"
      "-object" "rng-random,filename=/dev/urandom,id=guix-vm-rng"
      "-device" "virtio-rng-pci,rng=guix-vm-rng"