fix: add talos.config to the vApp Properties in VMware OVA

VMware vSphere doens't allow talos.config to be set when deploying the OVA
due to missing vApp properties. Added talos.config to the ovf template to include
talos.config to fix this.

Fixes talos-systems#3669

Signed-off-by: Joost Coelingh <joost.coelingh@eu.equinix.com>

cmd/installer/pkg/ova/ova.go

@@ -47,6 +47,14 @@ const ovfTpl = `<?xml version="1.0" encoding="UTF-8"?>
   <VirtualSystem ovf:id="vm">
     <Info>A virtual machine</Info>
     <Name>talos</Name>
+    <ProductSection ovf:required="false">
+      <Info>Talos Virtual Appliance</Info>
+      <Property ovf:userConfigurable="true" ovf:type="string"
+                ovf:key="talos.config" ovf:value="">
+        <Label>Talos config data</Label>
+        <Description>Inline Talos config</Description>
+      </Property>
+    </ProductSection>
     <OperatingSystemSection ovf:id="101" vmw:osType="other3xLinux64Guest">
       <Info>The kind of installed guest operating system</Info>
     </OperatingSystemSection>