coccinelle: put_device: Add a cast to an expression for an assignment

coccinelle: put_device: Add a cast to an expression for an assignment

Extend a when constraint in a SmPL rule so that an additional cast
is optionally excluded from source code searches for an expression
in assignments.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Suggested-by: Julia Lawall <Julia.Lawall@lip6.fr>
Link: https://lore.kernel.org/lkml/alpine.DEB.2.21.1902160934400.3212@hadrien/
Link: https://systeme.lip6.fr/pipermail/cocci/2019-February/005592.html
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>