MAINTAINERS: update maintainers list for Cypress

- Update maintainers' email with Infineon hosted email
- Add Chung-hsien Hsu as a maintainer

Signed-off-by: Chi-Hsien Lin <chi-hsien.lin@cypress.com>
Signed-off-by: Wright Feng <wright.feng@cypress.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201030085610.145679-1-chi-hsien.lin@cypress.com