[FrameworkBundle] Removed reference to FieldType in form.xml

| Q             | A
| ------------- | ---
| Bug fix?      | [yes]
| New feature?  | [no]
| BC breaks?    | [no]
| Deprecations? | [yes]
| Tests pass?   | [yes]
| Fixed tickets | 
| License       | MIT
| Doc PR        | 

Removed reference of deprecated FieldType class in FrameworkBundle form.xml configuragion.