drm/nouveau/mmu: rename from vmmgr (no binary change)

Switch to NVIDIA's name for the device.

The namespace of NVKM is being changed to nvkm_ instead of nouveau_,
which will be used for the DRM part of the driver.  This is being
done in order to make it very clear as to what part of the driver a
given symbol belongs to, and as a minor step towards splitting the
DRM driver out to be able to stand on its own (for virt).

Because there's already a large amount of churn here anyway, this is
as good a time as any to also switch to NVIDIA's device and chipset
naming to ease collaboration with them.

A comparison of objdump disassemblies proves no code changes.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/fifo/nvc0.c b/drivers/gpu/drm/nouveau/nvkm/engine/fifo/nvc0.c
index e8ef8cb..e5d1e96 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/fifo/nvc0.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/fifo/nvc0.c
@@ -35,7 +35,7 @@
 #include <subdev/timer.h>
 #include <subdev/bar.h>
 #include <subdev/fb.h>
-#include <subdev/vm.h>
+#include <subdev/mmu.h>
 
 #include <engine/dmaobj.h>
 #include <engine/fifo.h>