[VDA-ERC20] enableTransfer() fix

[tahpot]

Feedback from Hashlock audit.

[QA-01] Function should be named enableMint()

VeridaToken.enableTransfer() should be called enableMint.

The isTransferEnabled variable is only used to check if the transfer is a mint not if the token is being transfered so the name should be changed to match the functionality:

if (!isTransferEnabled) { 
            assembly { 
                if eq(iszero(sender), 0) { 
                    if eq(iszero(recipient), 0) { 
                        let ptr := mload(0x40) 
                        mstore(ptr, 0x69126dbd00000000000000000000000000000000000000000000000000000000) 
                        revert(ptr, 0x4) //revert TransferLimited() 
                    } 
                } 
            } 
        } 

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@ITStar10 I'd prefer the functionality be changed to check if the token is being transferred, it shouldn't care about mint.

[tahpot]

Upon further investigation, fix not required. Needed up update the logic so it matched enableTransfer(0