zephyr: docs: Add link to I2C doc
Update the Zephyr checklist to point to the completed I2C documentation.
BRANCH=none
TEST=Verify link with gerrit browse view
@@ -55,7 +55,7 @@ EC Feature | Ne
[Configure AP Power Sequencing (TODO)](./zephyr_template.md) | yes
[Configure USB-C (TODO)](./zephyr_template.md) | yes
[Configure Charger (TODO)](./zephyr_template.md) | yes
-[Configure I2C Buses (TODO)](./zephyr_template.md) | yes
+[Configure I2C Buses](./zephyr_i2c.md) | yes
[Configure Batteries (TODO)](./zephyr_template.md) | no
[Configure CrOS Board Information (CBI) (TODO)](./zephyr_template.md) | no
[Configure Keyboard (TODO)](./zephyr_template.md) | no
