video: tegra20: dc: pass DC id to internal devices

video: tegra20: dc: pass DC id to internal devices

Tegra SoC has 2 independent display controllers called DC_A and
DC_B, they are handled differently by internal video devices like
DSI and HDMI controllers so it is important for last to know
which display controller is used to properly set up registers.
To achieve this, a pipe field was added to pdata to pass display
controller id to internal Tegra SoC devices.

Tested-by: Agneli <poczt@protonmail.ch> # Toshiba AC100 T20
Tested-by: Robert Eckelmann <longnoserob@gmail.com> # ASUS TF101
Tested-by: Andreas Westman Dorcsak <hedmoo@yahoo.com> # ASUS Grouper E1565
Tested-by: Ion Agorria <ion@agorria.com> # HTC One X
Tested-by: Svyatoslav Ryhel <clamor95@gmail.com> # Nvidia Tegratab T114
Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>