MAINTAINERS: adjust file entry in ARM/LPC32XX SOC SUPPORT

Commit 51c87f0e ("dt-bindings: i2c: nxp,pnx-i2c: Convert to dtschema")
converts i2c-pnx.txt to nxp,pnx-i2c.yaml, but misses to adjust the file
entry in ARM/LPC32XX SOC SUPPORT.

Hence, ./scripts/get_maintainer.pl --self-test=patterns complains about a
broken reference.

Adjust the file entry in ARM/LPC32XX SOC SUPPORT after this conversion.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>