gnttab: fix compat query-size handling

The odd DEFINE_XEN_GUEST_HANDLE(), inconsistent with all other similar
constructs, should have caught my attention. Turns out it was needed for
the build to succeed merely because the corresponding #ifndef had a
typo. That typo in turn broke compat mode guests, by having query-size
requests of theirs wire into the domain_crash() at the bottom of the
switch().

Fixes: 8c3bb4d8ce ("xen/gnttab: Perform compat/native gnttab_query_size check")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Release-Acked-by: Oleksii Kurochko <Oleksii.kurochko@gmail.com>

xen/common/compat/grant_table.c

@@ -33,7 +33,6 @@ CHECK_gnttab_unmap_and_replace;
 #define xen_gnttab_query_size gnttab_query_size
 CHECK_gnttab_query_size;
 #undef xen_gnttab_query_size
-DEFINE_XEN_GUEST_HANDLE(gnttab_query_size_compat_t);
 
 DEFINE_XEN_GUEST_HANDLE(gnttab_setup_table_compat_t);
 DEFINE_XEN_GUEST_HANDLE(gnttab_transfer_compat_t);
@@ -111,7 +110,7 @@ int compat_grant_table_op(
     CASE(copy);
 #endif
 
-#ifndef CHECK_query_size
+#ifndef CHECK_gnttab_query_size
     CASE(query_size);
 #endif