platform/chrome: Don't make CHROME_PLATFORMS depends on X86 || ARM

The Chrome platform support depends on X86 || ARM because there are
only Chromebooks using those architectures. But only some drivers
depend on a given architecture, and the ones that do already have
a dependency on their specific Kconfig symbol entries.

An option is to also make CHROME_PLATFORMS depends on || COMPILE_TEST
but is more future proof to remove the dependency and let the drivers
be built in all architectures if possible to have more build coverage.
Acked-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJavier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: NLee Jones <lee.jones@linaro.org>

drivers/platform/chrome/Kconfig

@@ -4,7 +4,6 @@
 
 menuconfig CHROME_PLATFORMS
 	bool "Platform support for Chrome hardware"
-	depends on X86 || ARM
 	---help---
 	  Say Y here to get to see options for platform support for
 	  various Chromebooks and Chromeboxes. This option alone does