Remove Creative Commons license

After reviewing recent license changes, it was decided that the Apache
license is sufficient (since we were using CC-BY before, which is
equivilent). Switching to a single license for simplicity and uniform
licensing.

Bug: 70645094
Test: N/A
Change-Id: I0b7143eadf2eb17b1ebf0b58e84286f9f87283d9