smegw01: Fix wrong symbol override

board_mmc_get_env_part() is not called as the default implementation
of mmc_get_env_part() is used.

Fix this problem by directly calling mmc_get_env_part() instead.

Signed-off-by: Eduard Strehlau <eduard@lionizers.com>
Signed-off-by: Fabio Estevam <festevam@denx.de>
diff --git a/board/storopack/smegw01/smegw01.c b/board/storopack/smegw01/smegw01.c
index 20c0970..7b2c50a 100644
--- a/board/storopack/smegw01/smegw01.c
+++ b/board/storopack/smegw01/smegw01.c
@@ -102,7 +102,7 @@
 	return 0;
 }
 
-uint board_mmc_get_env_part(struct mmc *mmc)
+uint mmc_get_env_part(struct mmc *mmc)
 {
 	uint part = EXT_CSD_EXTRACT_BOOT_PART(mmc->part_config);