nouveau/uvmm: fix addr/range calcs for remap operations

dEQP-VK.sparse_resources.image_rebind.2d_array.r64i.128_128_8
was causing a remap operation like the below.

op_remap: prev: 0000003fffed0000 00000000000f0000 00000000a5abd18a 0000000000000000
op_remap: next:
op_remap: unmap: 0000003fffed0000 0000000000100000 0
op_map: map: 0000003ffffc0000 0000000000010000 000000005b1ba33c 00000000000e0000

This was resulting in an unmap operation from 0x3fffed0000+0xf0000, 0x100000
which was corrupting the pagetables and oopsing the kernel.

Fixes the prev + unmap range calcs to use start/end and map back to addr/range.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Fixes: b88baab8 ("drm/nouveau: implement new VM_BIND uAPI")
Cc: Danilo Krummrich <dakr@redhat.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240328024317.2041851-1-airlied@gmail.com

drivers/gpu/drm/nouveau/nouveau_uvmm.c

@@ -812,15 +812,15 @@ op_remap(struct drm_gpuva_op_remap *r,
 	struct drm_gpuva_op_unmap *u = r->unmap;
 	struct nouveau_uvma *uvma = uvma_from_va(u->va);
 	u64 addr = uvma->va.va.addr;
-	u64 range = uvma->va.va.range;
+	u64 end = uvma->va.va.addr + uvma->va.va.range;
 
 	if (r->prev)
 		addr = r->prev->va.addr + r->prev->va.range;
 
 	if (r->next)
-		range = r->next->va.addr - addr;
+		end = r->next->va.addr;
 
-	op_unmap_range(u, addr, range);
+	op_unmap_range(u, addr, end - addr);
 }
 
 static int