dt-bindings: add required macro definitions for SSPHY registers

Add required macro definitions for SSPHY registers to be accessed
for platforms having 11nm SSPHY.

Change-Id: Idc0de1e701f7c84a13a0795b6e3af9000563e324
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>