`Call`s not being resolved in if statements

[Turupawn]

Currently, the following fe code:

fn helper(x: u64) -> u64 { x + 1 }

pub fn test_if_else(x: u64) -> u64 {
    if x > 10 {
        let x : u64 = helper(x: 67)
        x
    } else {
        10
    }
}

Compiles to this:

function helper(x) -> ret {
  ret := add(x, 1)
}
function test_if_else(x) -> ret {
  let v0 := 0
  if gt(x, 10) {
    v0 := x
  }
  if iszero(gt(x, 10)) {
    v0 := 10
  }
  ret := v0
}

Notice the helper function is never called.