arm: am57xx: Define Android boot arguments

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
diff --git a/configs/am57xx_hs_evm_defconfig b/configs/am57xx_hs_evm_defconfig
index 91baa2b..5cd3456 100644
--- a/configs/am57xx_hs_evm_defconfig
+++ b/configs/am57xx_hs_evm_defconfig
@@ -20,6 +20,8 @@
 CONFIG_OF_BOARD_SETUP=y
 # CONFIG_ENV_IS_IN_FAT is not set
 CONFIG_ENV_IS_IN_MMC=y
+CONFIG_USE_BOOTARGS=y
+CONFIG_BOOTARGS="androidboot.serialno=${serial#} console=ttyS2,115200 androidboot.console=ttyS2 androidboot.hardware=am57xevmboard"
 CONFIG_SYS_CONSOLE_INFO_QUIET=y
 CONFIG_VERSION_VARIABLE=y
 CONFIG_BOARD_EARLY_INIT_F=y