samsung: misc: use board specific functions to set env board info

This change adds setup of environmental board info using
get_board_name() and get_board_type() functions for config
CONFIG_BOARD_TYPES.

This is useful in case of running many boards with just one config.

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Cc: Minkyu Kang <mk7.kang@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>