drivers: w1: style corrections-pointers-blanklines-comparisons

Correct pointer notations to include whitespace between
variable type and "*" character. Inserted blank line
after variable declatations at two locations.
Rearranged comparison within an if statment to have the
constant on the right-hand side.

Signed-off-by: Ben Werbowyj <ben.werbowyj@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>