docs(material/select): Disabling the select or individual options

Update documentation to include ReactiveForms use case

Fixes #24762

Author: jljohnson001

src/material/select/select.md

@@ -54,6 +54,9 @@ In some cases that `<mat-form-field>` may use the placeholder as the label (see
 
 It is possible to disable the entire select or individual options in the select by using the
 disabled property on the `<select>` or `<mat-select>` and the `<option>` or `<mat-option>` elements respectively.
+When working with Reactive Forms the select component can be disabled/enabled via form controls.
+This can be accomplished by creating a FormControl with the disabled property:
+`FormControl({value: '', disabled: true})` or `FormControl.enable()`, `FormControl.disable()`.
 
 <!-- example(select-disabled) -->