Sorry, you'll probably just have to wait for it to wear off in its own sweet time. Lidocaine doesn't have a specific antidote, although it's conceivable that increasing blood flow to the area might make it wear off slightly quicker (in addition to chewing, you could try holding a heat pack against your jaw?)
1) As already mentioned, most of your sense of 'taste' is actually mediated by smell.
2) You have taste receptors over your whole tongue, and probably the nerve block was only on one side, so you'll still taste with half your mouth.
3) The local anaesthetic you've been given is mainly intended to take out your trigeminal nerve, this being the one that transmits sensation and pain from your face. Your facial nerve does most of the facial movements, and clearly this is also partly taken out by the anaesthetic. Taste sensation is carried partly by the facial nerve (anterior two thirds of the tongue) and partly by the glossopharyngeal nerve (posterior third - and this nerve has a completely different course so the anaesthetic is unlikely to reach it). So you're only losing taste on the anterior two thirds of one side of your tongue, and as a previous poster mentioned, the different types of taste bud are spread all over the tongue, not particularly localised to different areas as once thought.
If taste has been taken out by the anaesthetic, i think it's likely to return later than facial movements and general sensation, but before pain, due to the diameter and myelination of the fibres - but i can't find any good information about what kind of nerve fibres they actually are, and i can't be bothered to go and fetch my copy of Gray's Anatomy (the medical textbook, not the TV series!). Regardless, you're unlikely to have a major taste deficit for the reasons given above, although psychosomatically it'll probably feel like you do because 'taste' is a mixture of loads of different things including the sensation of food in your mouth.
Hope you have a nice meal!