clevis-dracut: Trigger initramfs creation upon installation

Thanks Thomas Lange for shedding some light on this issue.

[
    Cherry-picked from: 7234651
    For buster stable: Lowered dependency on dracut to "Recommends:"
]

debian/clevis-dracut.triggers

@@ -0,0 +1 @@
+activate-noawait update-initramfs

debian/control

@@ -60,6 +60,8 @@ Architecture: all
 Depends: ${misc:Depends},
     clevis-systemd,
     dracut-network,
+Recommends:
+    dracut,
 Description: Dracut integration for clevis
  Clevis is a plugable framework for automated decryption. This package
  provides integration for the dracut initramfs to automatically unlock