drm/amdgpu: Fix one kernel-doc comment

Use colon to separate parameter name from their specific meaning.
silence the warning:

drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c:793: warning: Function parameter or member 'adev' not described in 'amdgpu_vm_pte_update_noretry_flags'
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c

@@ -783,7 +783,7 @@ int amdgpu_vm_pde_update(struct amdgpu_vm_update_params *params,
 /**
  * amdgpu_vm_pte_update_noretry_flags - Update PTE no-retry flags
  *
- * @adev - amdgpu_device pointer
+ * @adev: amdgpu_device pointer
  * @flags: pointer to PTE flags
  *
  * Update PTE no-retry flags when TF is enabled.