don't require symbol with enum type to be constant in fitNode (#23999)

fixes #23998

In `fitNode` the first symbol of a symchoice that expects an enum type
with the same enum type is given as the result of the `fitNode`. But
`getConstExpr` is also called on it, which will return a `nil` node for
nodes that aren't constant but have the enum type, like variables or
proc parameters. Instead we just return the node directly since it's
already typed.

Normally, this `if` branch in `fitNode` shouldn't exist since
`paramTypesMatch` handles it, but the way pure enum symbols work makes
it really impractical to check their ambiguity, which `paramTypesMatch`
won't like. If it causes problems for regular enums we can restrict this
branch to just pure enums until they are hopefully eventually removed.

0 files changed, 0 insertions, 0 deletions