refactor(v-input): remove disabled styles from readonly
refactor(v-input): remove disabled styles from readonly

resolves #4108

Webifi/vuetify,Phlow2001/vuetify,Webifi/vuetify,vuetifyjs/vuetify,Webifi/vuetify,Phlow2001/vuetify,Phlow2001/vuetify,vuetifyjs/vuetify,Phlow2001/vuetify,vuetifyjs/vuetify,vuetifyjs/vuetify