net: phy: aquantia: fix commenting format

Comment was erroneously added with /**, amend this to use /* as it is
not a kernel-doc.

Reported-by: kernel test robot <[e-mail]>
Closes: https://lore.kernel.org/oe-kbuild-all/[e-mail]/
Signed-off-by: Aryan Srivastava <[e-mail]>
Reviewed-by: Simon Horman <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

drivers/net/phy/aquantia/aquantia_main.c

···
 	if (!phydev->link || phydev->autoneg == AUTONEG_DISABLE)
 		return 0;
 
-	/**
-	 * The status register is not immediately correct on line side link up.
+	/* The status register is not immediately correct on line side link up.
 	 * Poll periodically until it reflects the correct ON state.
 	 * Only return fail for read error, timeout defaults to OFF state.
 	 */
···
 	if (!phydev->link || phydev->autoneg == AUTONEG_DISABLE)
 		return 0;
 
-	/**
-	 * The status register is not immediately correct on line side link up.
+	/* The status register is not immediately correct on line side link up.
 	 * Poll periodically until it reflects the correct ON state.
 	 * Only return fail for read error, timeout defaults to OFF state.
 	 */