memory: tegra: Delete dead debugfs checking code

The debugfs_create_dir() function does not return NULL, it returns error
pointers.  But in normal situations like this where the caller is not
dereferencing "emc->debugfs.root" then we are not supposed to check the
return.  So instead of fixing these checks, we should delete them.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YMCQDTSyG8UuQoh0@mwandaSigned-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>

drivers/memory/tegra/tegra124-emc.c

@@ -1269,10 +1269,6 @@ static void emc_debugfs_init(struct device *dev, struct tegra_emc *emc)
 	}
 
 	emc->debugfs.root = debugfs_create_dir("emc", NULL);
-	if (!emc->debugfs.root) {
-		dev_err(dev, "failed to create debugfs directory\n");
-		return;
-	}
 
 	debugfs_create_file("available_rates", 0444, emc->debugfs.root, emc,
 			    &tegra_emc_debug_available_rates_fops);

drivers/memory/tegra/tegra20-emc.c

@@ -776,10 +776,6 @@ static void tegra_emc_debugfs_init(struct tegra_emc *emc)
 	}
 
 	emc->debugfs.root = debugfs_create_dir("emc", NULL);
-	if (!emc->debugfs.root) {
-		dev_err(emc->dev, "failed to create debugfs directory\n");
-		return;
-	}
 
 	debugfs_create_file("available_rates", 0444, emc->debugfs.root,
 			    emc, &tegra_emc_debug_available_rates_fops);

drivers/memory/tegra/tegra210-emc-core.c

@@ -1759,10 +1759,6 @@ static void tegra210_emc_debugfs_init(struct tegra210_emc *emc)
 	}
 
 	emc->debugfs.root = debugfs_create_dir("emc", NULL);
-	if (!emc->debugfs.root) {
-		dev_err(dev, "failed to create debugfs directory\n");
-		return;
-	}
 
 	debugfs_create_file("available_rates", 0444, emc->debugfs.root, emc,
 			    &tegra210_emc_debug_available_rates_fops);

drivers/memory/tegra/tegra30-emc.c

@@ -1354,10 +1354,6 @@ static void tegra_emc_debugfs_init(struct tegra_emc *emc)
 	}
 
 	emc->debugfs.root = debugfs_create_dir("emc", NULL);
-	if (!emc->debugfs.root) {
-		dev_err(emc->dev, "failed to create debugfs directory\n");
-		return;
-	}
 
 	debugfs_create_file("available_rates", 0444, emc->debugfs.root,
 			    emc, &tegra_emc_debug_available_rates_fops);