Remap PS key to BUTTON_MODE

In an earlier commit, ag/4071802, (Change-Id:
I33e922a2c52582f44d65f20024d7dca1f9d05a5e), this particular file was
overlooked.
Quick fix here to make everything consistent. We will add the other
variants of these devices in the future.

Test: partial cherry-pick from Sony CL on aosp
Bug: 79881694
Change-Id: I8ab46fde8650724464b1e799cd948682c56e5b52
Merged-In: I8ab46fde8650724464b1e799cd948682c56e5b52