make: don't evaluate several simple modifiers in parse-only mode

This affects the modifiers ':E', ':H', ':P', ':Q', ':R', ':T', ':hash',
':q', ':range', ':tl', ':ts', ':tu', and ':u'.  All these modifiers are
side-effect free.

Skipping the evaluation for these modifiers is purely for code
consistency and performance.

No functional change.

(rillig)