checker: fix fn call with option call argument in autofree mode (fix #19495)

[yuyi98]

This PR fix fn call with option call argument in autofree mode (fix #19495).

import os

fn maybe_error() !string {
	return 'string'
}

fn return_string_result() ! {
	os.write_file('./test.txt', maybe_error()!)!
}

fn main() {
	return_string_result() or {
		println(err.msg())
		exit(1)
	}
}

PS D:\Test\v\tt1> v -autofree run .

[spytheman]

That indeed fixes the compilation, and may work for now, but consider, that the result of the callexpr arg, may be a string itself, or an array, or a map, or another struct, that was allocated inside that function:

import rand
fn f() !string { return rand.string(5) + '8' }
fn g(x string, y string) string { return x + y }
s := g( f()!, f()! )
println(s)

Here, both f()! and f()! will return different dynamically created strings, that will have to be freed, after g() finishes.

i.e. the cost of skipping those callexpression arguments, is allowing a preventable leak.

[yuyi98]

OK，I see.

[spytheman]

Good for now (a compiling program is better than one failing with a cgen error), but it should be fixed properly later, so that the result is freed, for -autofree to work.