drm/amdgpu: remove unneeded semicolon

Eliminate the following coccicheck warning:
./drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c:2725:16-17: Unneeded semicolon
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Reviewed-by: Guchun Chen <guchun.chen@amd.com>
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_ras.c

@@ -2722,7 +2722,7 @@ struct amdgpu_ras* amdgpu_ras_get_context(struct amdgpu_device *adev)
 int amdgpu_ras_set_context(struct amdgpu_device *adev, struct amdgpu_ras* ras_con)
 {
 	if (!adev)
-	return -EINVAL;;
+		return -EINVAL;
 
 	adev->psp.ras_context.ras = ras_con;
 	return 0;