i3c: Remove superfluous FIXME

I2C adapters can already change timeout and retry parameters via IOCTL.
This allows for better tuning to workloads compared to per-adapter
defaults. So, the FIXME is not needed.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20250923203557.18298-2-wsa+renesas@sang-engineering.com


Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>