* Sponsors signal unease on Qatar 2022 bribe allegations
* Allegations cloud build-up to Brazil tournament this week
* Sponsors, broadcasters would benefit from move to another venue (Adds Kia comment)
By Keith Weir and Ossian Shine
LONDON/RIO DE JANEIRO June 8 (Reuters) - Sponsors Adidas , Sony, Visa and Coca-Cola on Sunday called on soccer's rulers to deal thoroughly with allegations ...