Use g_new() & friends where that makes obvious sense

g_new(T, n) is neater than g_malloc(sizeof(T) * n).  It's also safer,
for two reasons.  One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.

This commit only touches allocations with size arguments of the form
sizeof(T).

Patch created mechanically with:

    $ spatch --in-place --sp-file scripts/coccinelle/use-g_new-etc.cocci \
	     --macro-file scripts/cocci-macro-file.h FILES...

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20220315144156.1595462-4-armbru@redhat.com>
Reviewed-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>

qom/qom-qmp-cmds.c

@@ -49,7 +49,7 @@ ObjectPropertyInfoList *qmp_qom_list(const char *path, Error **errp)
 
     object_property_iter_init(&iter, obj);
     while ((prop = object_property_iter_next(&iter))) {
-        ObjectPropertyInfo *value = g_malloc0(sizeof(ObjectPropertyInfo));
+        ObjectPropertyInfo *value = g_new0(ObjectPropertyInfo, 1);
 
         QAPI_LIST_PREPEND(props, value);