The world’s most advanced contract chipmaker has severed its ties with a Singapore-based company after a client review exposed a potential breach of US export controls, according to people familiar with the matter.Taiwan Semiconductor Manufacturing Company (TSMC) ended its relationship with PowerAIR, a low-key Singaporean firm, following a client check triggered by the discovery of a TSMC chip in a Huawei Technologies artificial intelligence (AI) processor, three sources said.PowerAIR is the sec...