The value of CONFIG_BAUDRATE is treated as string and put as initial value of
environment variable. If it begin with '(', it is wrongly parsed to 0 in number.
So I removed '(' and ')'.
Signed-off-by: Tetsuyuki Kobayashi <koba@kmckk.co.jp>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>