The Huawei cinder driver needs to mask out any instances of the
CHAPPASSWORD in the logs [1]. This patch adds to the sanitize
keys list so that cinder may make use of the common mask_password
function.
[1] https://review.openstack.org/#/c/271595
Change-Id: I679e576121e2a74ac6684ecc634690708cf39315
Partial-Bug: #1535706