drm/nouveau/mmu/tu102-: remove write to 0x100e68 during tlb invalidate

This was cargo-culted from traces of RM when the code was written, but
we probably shouldn't be touching NV_PFB regs while GSP-RM is running.

From traces, it looks like NVIDIA dropped this sometime between 510.54
and 515.48.07, so I guess we can too.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230918202149.4343-2-skeggsb@gmail.com

drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmtu102.c

@@ -37,7 +37,6 @@ tu102_vmm_flush(struct nvkm_vmm *vmm, int depth)
 
 	nvkm_wr32(device, 0xb830a0, vmm->pd->pt[0]->addr >> 8);
 	nvkm_wr32(device, 0xb830a4, 0x00000000);
-	nvkm_wr32(device, 0x100e68, 0x00000000);
 	nvkm_wr32(device, 0xb830b0, 0x80000000 | type);
 
 	nvkm_msec(device, 2000,