Stocks weaken on dimming hopes for Iran deal, mixed quarterly earnings
* Stocks ease as oil prices climb * Tesla, IBM and Lockheed Martin down after earnings * Texas Instruments gains after results * Indexes off: Dow 0.48%, S&P 500 0.49%, Nasdaq 0.95% (Updates to afternoon New York trading) By Chuck Mikolajczak and Niket Nishant NEW YORK, April 23 (Reuters) – US stocks fell in choppy…