Revert "net: stmicro: fix a missing check of clk_prepare"

This reverts commit f86a3b83.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be incorrect for the reasons
below, so it must be reverted.  It will be fixed up "correctly" in a
later kernel change.

The original commit causes a memory leak when it is trying to claim it
is properly handling errors.  Revert this change and fix it up properly
in a follow-on commit.

Cc: Kangjie Lu <kjlu@umn.edu>
Cc: David S. Miller <davem@davemloft.net>
Fixes: f86a3b83 ("net: stmicro: fix a missing check of clk_prepare")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210503115736.2104747-21-gregkh@linuxfoundation.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/ethernet/stmicro/stmmac/dwmac-sunxi.c

@@ -50,9 +50,7 @@ static int sun7i_gmac_init(struct platform_device *pdev, void *priv)
 		gmac->clk_enabled = 1;
 	} else {
 		clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
-		ret = clk_prepare(gmac->tx_clk);
-		if (ret)
-			return ret;
+		clk_prepare(gmac->tx_clk);
 	}
 
 	return 0;