Adjust version of required qubes-gui-agent

The "qubes-sysinit: set GUI_OPTS in gui-agent-linux" commit breaks
gui-agent-linux lacking its counterpart. Express this in the package
metadata.

QubesOS/qubes-issues#5662

debian/control

@@ -79,7 +79,7 @@ Conflicts:
     qubes-core-agent-linux,
     firewalld,
     qubes-core-vm-sysvinit,
-    qubes-gui-agent (<< 4.1.0-1)
+    qubes-gui-agent (<< 4.1.6-1)
 Description: Qubes core agent
  This package includes various daemons necessary for qubes domU support,
  such as qrexec services.

rpm_spec/core-agent.spec.in

@@ -145,7 +145,7 @@ Provides:   qubes-core-vm = %{version}-%{release}
 Obsoletes:  qubes-core-vm < 4.0.0
 Provides:	qubes-core-vm-doc = %{version}-%{release}
 Obsoletes:	qubes-core-vm-doc < 4.0.0
-Conflicts:	qubes-gui-agent < 4.1.0
+Conflicts:	qubes-gui-agent < 4.1.6
 BuildRequires: gcc
 BuildRequires: pandoc
 BuildRequires: xen-devel