tegra: Whistler board support

Whistler is a highly configurable Tegra evaluation and development board.
This change adds support for the following specific configuration:

E1120 motherboard
E1108 CPU board
E1116 PMU board

The motherboard configuration switches are set as follows:
SW1=0 SW2=0 SW3=5
S1/S2/S3/S4 all on, except S3 7/8 are off.

Other combinations of daugher boards may work to varying degrees, but will
likely require some SW adjustment.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/boards.cfg b/boards.cfg
index a723f67..055dbbc 100644
--- a/boards.cfg
+++ b/boards.cfg
@@ -231,6 +231,7 @@
 harmony                      arm         armv7       harmony             nvidia         tegra2
 seaboard                     arm         armv7       seaboard            nvidia         tegra2
 ventana                      arm         armv7       ventana             nvidia         tegra2
+whistler                     arm         armv7       whistler            nvidia         tegra2
 u8500_href                   arm         armv7       u8500               st-ericsson    u8500
 actux1_4_16                  arm         ixp         actux1              -              -           actux1:FLASH2X2
 actux1_4_32                  arm         ixp         actux1              -              -           actux1:FLASH2X2,RAM_32MB