CHROMIUM: iommu/rockchip: Fix TLB flush of secondary IOMMUs

CHROMIUM: iommu/rockchip: Fix TLB flush of secondary IOMMUs

Due to the bug in current code, only first IOMMU has the TLB lines
flushed in rk_iommu_zap_lines. This patch fixes the inner loop to
execute for all IOMMUs and properly flush the TLB.

BUG=chrome-os-partner:55135
TEST=compile

Change-Id: Ica2d4b0cc3d3cbc88c70ad541dc00883f1b4e90c
Signed-off-by: Tomasz Figa <tfiga@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/371098
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Randy Li <randy.li@rock-chips.com>