Fix locals() interaction with generic types

Follow the same logic as semTupleFieldsConstr and only skip skVar since
we're gonna add a nkDefer anyway.

Fixes #8985

tests/misc/tlocals.nim

@@ -9,3 +9,22 @@ proc simple[T](a: T) =
 
 simple(1)
 
+type Foo2[T]=object
+  a2: T
+
+proc numFields*(T: typedesc[tuple|object]): int=
+  var t:T
+  for _ in t.fields: inc result
+
+proc test(baz: int, qux: var int): int =
+  var foo: Foo2[int]
+  let bar = "abc"
+  let c1 = locals()
+  doAssert numFields(c1.foo.type) == 1
+  doAssert c1.bar == "abc"
+  doAssert c1.baz == 123
+  doAssert c1.result == 0
+  doAssert c1.qux == 456
+
+var x1 = 456
+discard test(123, x1)