Input: two merge window build fixes

[Arnd Bergmann]

Hi Dmitry,

I ran into two new build regressions in the input subsystem with
today's linux-next, maybe you can apply these fixes before sending
off the pull request for v4.7.

	Arnd

[PATCH 1/2] Input: atmel captouch depends on i2c
[PATCH 2/2] Input: migor-ts: mark PM functions as __maybe_unused