w1: Remove unneeded use of assert() and remove w1_log.h

The only use of assert() is in matrox_w1.c and is used to check the input
to probe() from the PCI subsystem for NULL values, these are guaranteed
to be populated and no other PCI driver makes this check, remove this.

As this was the only definition in w1_log.h, remove this also.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>