staging:nvec:nvec_ps2.c: Prefering kzalloc(sizeof(*ser_dev)...) over...

staging:nvec:nvec_ps2.c: Prefering kzalloc(sizeof(*ser_dev)...) over kzalloc(sizeof(struct serio)...)

Prefer kzalloc(sizeof(*ser_dev)...) over kzalloc(sizeof(struct
serio)...) as reported by checkpatch.pl.

Signed-off-by: Arushi Singhal <arushisinghal19971997@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>