This is just a nickname. The nickname table should be in the last of your full dts. It is defined as below.
host1x {
i2c@546c0000 {
ina3221x: ina3221x@40 {
compatible = “ti,ina3221x”;
reg = <0x40>;
Thus, the ina3221x is above case should be ina3221x@40.