Staging: sm7xx: preferred form for passing a size to memory allocation routines

The preferred form for passing a size of a struct is the following:
p = kmalloc(sizeof(*p), ...);
Please refer Documentation/Codingstyle chapter 14

Signed-off-by: anish kumar <anish198519851985@gmail.com>
Acked-by: Harry Wei <harryxiyou@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>