V4L/DVB: IR: minor fixes

* lirc: Don't propagate reset event to userspace
* lirc: Remove strange logic from lirc that would make first sample always be pulse
* Make TO_US macro actualy print what it should.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>