env_mmc: Allow SPL to use any MMC device to load/save the environment

SPL has been restricted to use only dev 0 based on the assumption that only
one MMC device is registered. This is not always the case and many
platforms now register several devices as expected by the spl mmc boot code
For those platform SPL_ENV_SUPPORT is broken if dev is forced to 0.

A word of warning: this commit may break SPL_ENV_SUPPORT on platforms that
do not register the same MMC controllers in SPL and in u-boot (mostly iMX6
based platforms). Fortunately none of those activate SPL_ENV_SUPPORT in
their default configuration.
Signed-off-by: NJean-Jacques Hiblot <jjhiblot@ti.com>

common/env_mmc.c

@@ -82,10 +82,6 @@ static int mmc_set_env_part(struct mmc *mmc)
 	int dev = mmc_get_env_dev();
 	int ret = 0;
 
-#ifdef CONFIG_SPL_BUILD
-	dev = 0;
-#endif
-
 	env_mmc_orig_hwpart = mmc_get_blk_desc(mmc)->hwpart;
 	ret = blk_select_hwpart_devnum(IF_TYPE_MMC, dev, part);
 	if (ret)
@@ -116,9 +112,6 @@ static void fini_mmc_for_env(struct mmc *mmc)
 #ifdef CONFIG_SYS_MMC_ENV_PART
 	int dev = mmc_get_env_dev();
 
-#ifdef CONFIG_SPL_BUILD
-	dev = 0;
-#endif
 	blk_select_hwpart_devnum(IF_TYPE_MMC, dev, env_mmc_orig_hwpart);
 #endif
 }
@@ -223,10 +216,6 @@ void env_relocate_spec(void)
 	ALLOC_CACHE_ALIGN_BUFFER(env_t, tmp_env1, 1);
 	ALLOC_CACHE_ALIGN_BUFFER(env_t, tmp_env2, 1);
 
-#ifdef CONFIG_SPL_BUILD
-	dev = 0;
-#endif
-
 	mmc = find_mmc_device(dev);
 
 	errmsg = init_mmc_for_env(mmc);
@@ -306,10 +295,6 @@ void env_relocate_spec(void)
 	int dev = mmc_get_env_dev();
 	const char *errmsg;
 
-#ifdef CONFIG_SPL_BUILD
-	dev = 0;
-#endif
-
 	mmc = find_mmc_device(dev);
 
 	errmsg = init_mmc_for_env(mmc);