drm/amd/display: fix header for RN clk mgr

[why]
Should always MP0_BASE for any register definition from MP per-IP header files.
I belive the reason the linux version of MP1_BASE works is The 0th element of the 0th table
of that is identical to the corrisponding value of MP0_BASE in the renoir offset header file.
The reason we should only use MP0_BASE is There is only one set of per-IP headers MP
that includes all register definitions related to SMU IP block. This IP includes MP0, MP1, MP2
and  an ecryption engine that can be used only by MP0. As a result all register definitions from
MP file should be based only on MP0_BASE data.

[How]
Change MP1_BASE to MP0_BASE

Signed-off-by: joseph gravenor <joseph.gravenor@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Reviewed-by: Roman Li <Roman.Li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>