add script to setup android envirenment

This sets the android environment by creating a branch in the Android bootloader-binaries path

This was copied from [1] based on sha-1: 7957a2ca265402b5ccdfa69f6a80d99732dbbe7e

[1] https://gitlab.com/mediatek/aiot/bsp/build-bootloaders

Signed-off-by: Julien Masson jmasson@baylibre.com Signed-off-by: souajih souajih@baylibre.com