Subject: vscsi >2TB build fix

MAINTENANCE_{IN,OUT} got introduced only in 2.6.19, but I failed to
notice that because we have this backported to our 2.6.16-based
kernels.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>

--- a/drivers/xen/scsiback/emulate.c
+++ b/drivers/xen/scsiback/emulate.c
@@ -452,8 +452,10 @@ void scsiback_emulation_init(void)
 	/*NO_EMULATE(PERSISTENT_RESERVE_IN); *//*0x5e*/
 	/*NO_EMULATE(PERSISTENT_RESERVE_OUT); *//*0x5f*/
 	/*           REPORT_LUNS             *//*0xa0*//*Full emulaiton*/
+#ifdef MAINTENANCE_IN
 	NO_EMULATE(MAINTENANCE_IN);           /*0xa3*/ /* IFT alua */
 	NO_EMULATE(MAINTENANCE_OUT);       /*0xa4*/ /* IFT alua */
+#endif
 	NO_EMULATE(MOVE_MEDIUM);           /*0xa5*/ /* ch */
 	NO_EMULATE(EXCHANGE_MEDIUM);       /*0xa6*/ /* ch */
 	/*NO_EMULATE(READ_12);               *//*0xa8*/