drm/amdgpu: use the same HDP flush registers for all nbio 2.3.x

Align RDNA2.x with other asics. One HDP bit per SDMA instance,
aligned with firmware. This is effectively a revert of
commit 369b7d04baf3 ("drm/amdgpu/nbio2.3: don't use GPU_HDP_FLUSH bit 12").
On further discussions with the relevant hardware teams,
re-align the bits for SDMA.

Fixes: 369b7d04baf3 ("drm/amdgpu/nbio2.3: don't use GPU_HDP_FLUSH bit 12")
Reviewed-by: Kent Russell <kent.russell@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amdgpu/nbio2.3: don't use GPU_HDP_FLUSH bit 12

It's used internally by firmware. Using it in the driver
could conflict with firmware.

v2: squash in fix for navi1x (Alex)

Reviewed-by: James Zhu <James.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amdgpu: switch to new amdgpu_nbio structure

no functional change, just switch to new structures

Signed-off-by: Hawking Zhang <Hawking.Zhang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/amdgpu: add nbio v2.3 for navi10 (v4)

nbio handles bus io functionality.

v1: add place holder and initial basic nbio v2.3 functions (Ray)
v2: implements and expose all functions in format of nbio_v2_3_funcs (Hawking)
v3: squash in updates (Alex)
v4: whitespace fix (Alex)

Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Hawking Zhang <Hawking.Zhang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>