Add registry tweak to make PDOs ejectable
Add registry tweak to make PDOs ejectable

Add a registry tweak called 'AllowPdoEject' so that PDOs can be made
ejectable and rename the tweak to make PDOs removable to 'AllowPdoRemove'
to bring it in line.

Signed-off-by: Paul Durrant <dba6cd059c0054f8a3c62ba902cd9d7238853ee4@citrix.com>

omeg/xenbus,rneilturner/xenbus,MarkKMueller/xenbus,QubesOS/qubes-vmm-xen-win-pvdrivers-xenbus,rneilturner/xenbus,omeg/xenbus,QubesOS/qubes-vmm-xen-win-pvdrivers-xenbus,QubesOS/qubes-vmm-xen-win-pvdrivers-xenbus,omeg/xenbus,MarkKMueller/xenbus,rneilturner/xenbus,MarkKMueller/xenbus