virtio-blk: avoid qdev property definition duplication

It becomes unwiedly to duplicate all virtio-blk qdev property
definitions due to an #ifdef.  The C preprocessor syntax makes it a
little hard to resolve this cleanly but we can extract the #ifdef and
call a macro it defines later.

Avoiding duplication is important since it will only get worse when we
move the x-data-plane qdev property here too.  We'd have a combinatorial
explosion since x-data-plane has its own #ifdef.
Suggested-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>

include/hw/virtio/virtio-blk.h

@@ -156,21 +156,19 @@ typedef struct VirtIOBlockReq {
         DEFINE_VIRTIO_COMMON_FEATURES(_state, _field)
 
 #ifdef __linux__
-#define DEFINE_VIRTIO_BLK_PROPERTIES(_state, _field)                          \
-        DEFINE_BLOCK_PROPERTIES(_state, _field.conf),                         \
-        DEFINE_BLOCK_CHS_PROPERTIES(_state, _field.conf),                     \
-        DEFINE_PROP_STRING("serial", _state, _field.serial),                  \
-        DEFINE_PROP_BIT("config-wce", _state, _field.config_wce, 0, true),    \
-        DEFINE_PROP_BIT("scsi", _state, _field.scsi, 0, true),                \
-        DEFINE_PROP_IOTHREAD("x-iothread", _state, _field.iothread)
+#define DEFINE_VIRTIO_BLK_PROPERTIES_LINUX(_state, _field) \
+        DEFINE_PROP_BIT("scsi", _state, _field.scsi, 0, true),
 #else
+#define DEFINE_VIRTIO_BLK_PROPERTIES_LINUX(_state, _field)
+#endif
+
 #define DEFINE_VIRTIO_BLK_PROPERTIES(_state, _field)                          \
+        DEFINE_VIRTIO_BLK_PROPERTIES_LINUX(_state, _field)                    \
         DEFINE_BLOCK_PROPERTIES(_state, _field.conf),                         \
         DEFINE_BLOCK_CHS_PROPERTIES(_state, _field.conf),                     \
         DEFINE_PROP_STRING("serial", _state, _field.serial),                  \
         DEFINE_PROP_BIT("config-wce", _state, _field.config_wce, 0, true),    \
         DEFINE_PROP_IOTHREAD("x-iothread", _state, _field.iothread)
-#endif /* __linux__ */
 
 void virtio_blk_set_conf(DeviceState *dev, VirtIOBlkConf *blk);