Add USB2 PHY "pipe phystatus" register support

We want the following two patches ported to upstream kernel:

• https://github.com/radxa/kernel/commit/b50ae2d265b93435196e7d3ecc959f738c6f0cd2
• https://github.com/radxa/kernel/commit/b88a2bdd105157b397e6f0893a5a5214982a6b3c