arm/davinci: spl - automatic boot device selection (v3)

This patch allow us to have a universal spl that detects a boot
device and select a corresponding boot algorithm for main u-boot part
(SOC_DA8XX only)

Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com>
arm/davinci: spl - add compressed u-boot image support (v3)

Motivation:
 * we have a board with 128 Kb spi flash, so normal u-boot.ais does not
   fit on it.

This patch add support of compressed 2-nd u-boot stage. To create a compressed
ais image its required:
 * define CONFIG_SPL_GUNZIP_SUPPORT --- enable compressed ais image supports
 * define CONFIG_SPL_GUNZIP_MAX_SIZE --- define a maximum size of compressed
   u-boot part
 * define CONFIG_SPL_GUNZIP_LOAD_ADDR --- memory address to load compressed
   u-boot part (CONFIG_SPL_GUNZIP_LOAD_ADDR region should not overlap with
   CONFIG_SYS_TEXT_BASE region)
 * use: make u-boot-gzip.ais to get a compressed ais image

Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com>
arm/davinci/da850: initial trikboard support

Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com>
arm/davinci: add UART0/1 CLKID, add UART1 PSRC

Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com>
arm/davinci: add spi0 punmuxes

Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com>
arm/davinci/da850: initial trikboard support

Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com>
add I2C command
CMD BOOT ARGS
SPI flash boot (correct enviroment size & initialize console fix)
spi chip select bug fix
add some func
additional u-boot env
gpio red led & back_light switch on while booting
ddr size 128 mb
remove backlight
support ext4 fs boot
update memory timings (chip: mt47h128m16rt-25eit)
Test stand default enviroment
add some default parameters