i2c: davinci: Free requested IRQ in remove

The freed IRQ is not necessary the one requested in probe.
Even if it was, with two or more i2c-controllers it will fails anyway.

Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: stable@kernel.org