ARM: tegra: fix "bootp" issue for Tegra124 too

ARM: tegra: fix "bootp" issue for Tegra124 too

Fix the timeout issue after running "bootp" command in U-Boot console.

TXFIFOTHRES bits of TXFILLTUNING register should be set to 0x10 after a
controller reset and before RUN bit is set (per technical reference
manual).

Signed-off-by: Jim Lin <jilin@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>