treewide: Unify Google branding

Branding changes to unify and update Chrome OS to ChromeOS (removing the
space).

This CL also includes changing Chromium OS to ChromiumOS as well.

BUG=None
TEST=N/A

Change-Id: I39af9f1069b62747dbfeebdd62d85fabfa655dcd
Signed-off-by: Jon Murphy <jpmurphy@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/65479
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Singer <felixsinger@posteo.net>

src/vendorcode/google/chromeos/chromeos.h

@@ -38,7 +38,7 @@ void chromeos_set_ramoops(void *ram_oops, size_t size);
 enum cb_err get_dsm_calibration_from_key(const char *key, uint64_t *value);
 
 /*
- * Declaration for mainboards to use to generate ACPI-specific Chrome OS needs.
+ * Declaration for mainboards to use to generate ACPI-specific ChromeOS needs.
  */
 void chromeos_acpi_gpio_generate(void);