[PATCH synaptics] Init num_touches to 0 on start

[Chase Douglas]

On 04/25/2012 05:36 PM, Peter Hutterer wrote:
> We implicitly rely on this already since we calloc the struct. Do it
> expliclity on DeviceOn().
> 
> Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
> ---
> This half of the fix to 49161 a bit redundant but better safe than sorry,
> they say.

I have not problems with it, but this is basically how things are done
all over the X stack. It's assumed structs are calloc'd where it isn't
obvious pretty much. Does this mean we have to take up arms against all
uninitialized members? :)

Reviewed-by: Chase Douglas <chase.douglas at canonical.com>