This seems like a job for Object.assign:
const output = Object.assign({}, ...params.map(p => ({[p.name]: p.input})));
Edited to wrap as a function similar to OP's, this would be:
const toHash = (array, keyName, valueName) =>
Object.assign({}, ...array.map(o => ({[o[keyName]]: o[valueName]})));
(Thanks to Ben Steward, good thinking...)