Broadcom's AI revenue surged 77% year-over-year, boosting its stock after a volatile 2021 so far.Broadcom's custom AI chips, designed with cloud companies, offer lower-cost options than Nvidia.Analysts predict the ASIC market will nearly double this year.Broadcom's AI business reported $4.1 billion in revenue in the last quarter, a 77% uptick compared to the same period last year.