drivers: i2c_rtio: MCUX LPflexcomm determine by inst

Determine if lpflexcomm wrapped lpi2c by instance and connect
irq differently dependending on that to support platforms with
both flexcomm wrapped and unwrapped lpi2c's.

Applying c1286a8d8d425805fcceb3b872325fb4c439a572 to RTIO version.

Authored-by: Declan Snyder <declan.snyder@nxp.com>
Signed-off-by: Luis Ubieda <luisf@croxel.com>