media: sir_ir: remove broken driver

This driver is a port of the lirc_sir driver to rc-core. However, for
this driver I could not find any hardware to test, so it was done without
testing. This is a mistake.

There are clear bugs in the code. For example the two arguments
to ktime_us_delta() are reversed, which means the result is garbage.

The driver has been in the kernel for four years, and noone has ever
reported an issue. So, remove this driver.

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>