env: sf: Use ENV_VALID enum names instead of literals

The function env_sf_init_addr() assigns number literals (1) instead of
ENV_VALID to gd->env_valid. Fix this.

Signed-off-by: Marek BehĂșn <marek.behun@nic.cz>
Reviewed-by: Simon Glass <sjg@chromium.org>
1 file changed