Cope with GranterPermitAccess() failing

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Fix stupid typo (and add an error warning)

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Remove some debug spew on grant table allocation failures

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