In some cases local pointers are used to cast void pointers passed to
the function. Those unnecessary local pointers are also removed.

This patch was inspired by Joe Perches' patch
[PATCH net-next 1/2] wireless: Remove casts of void *;
and the comments from Julian Calaby.
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Cc: Joe Perches <joe@perches.com>
Cc: Julian Calaby <julian.calaby@gmail.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>