Prevent keyboards from being recognized as a stylus

We are getting reports of keyboards and other peripherals being
misconfigured as a stylus, because they report support for stylus
buttons.

To eliminate some of these misconfigurations, prevent anything detected
as a alphabetical keyboard from being categorized as a stylus.

Bug: 293996865
Test: None
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:3c28b94505b5c6edaeb7e0df3ace7cf3f8125887)
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:0824e928e70da8c0fb78d9793a5a3f8f4f8f9db0)
Merged-In: I3f071d2ac6a2b70abc1130b4d5df1509452bb63b
Change-Id: I3f071d2ac6a2b70abc1130b4d5df1509452bb63b