i2c_intel_mid: Fix slash in sysfs name

This gets caught by the new sanity check code. Instead of the slash use a
different symbol. This was originally found by Major Lee who proposed a
rather more complex patch which changed the name according to the chip
type.

On the basis that we are in a late -rc and making Linus grumpy isn't always
a good idea (however fun) this is a simple alternative.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>