qapi: Replace qobject_to_X(o) by qobject_to(X, o)

This patch was generated using the following Coccinelle script:

@@
expression Obj;
@@
(
- qobject_to_qnum(Obj)
+ qobject_to(QNum, Obj)
|
- qobject_to_qstring(Obj)
+ qobject_to(QString, Obj)
|
- qobject_to_qdict(Obj)
+ qobject_to(QDict, Obj)
|
- qobject_to_qlist(Obj)
+ qobject_to(QList, Obj)
|
- qobject_to_qbool(Obj)
+ qobject_to(QBool, Obj)
)

and a bit of manual fix-up for overly long lines and three places in
tests/check-qjson.c that Coccinelle did not find.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-Id: <20180224154033.29559-4-mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: swap order from qobject_to(o, X), rebase to master, also a fix
to latent false-positive compiler complaint about hw/i386/acpi-build.c]
Signed-off-by: Eric Blake <eblake@redhat.com>

block.c

@@ -1457,7 +1457,7 @@ static QDict *parse_json_filename(const char *filename, Error **errp)
         return NULL;
     }
 
-    options = qobject_to_qdict(options_obj);
+    options = qobject_to(QDict, options_obj);
     if (!options) {
         qobject_decref(options_obj);
         error_setg(errp, "Invalid JSON object given");
@@ -2433,7 +2433,7 @@ BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp)
         }
         visit_complete(v, &obj);
 
-        qdict = qobject_to_qdict(obj);
+        qdict = qobject_to(QDict, obj);
         qdict_flatten(qdict);
 
         /* bdrv_open_inherit() defaults to the values in bdrv_flags (for