All hospitals are run like this if you read the other news stories related to this, essentially more patients are visiting the A&E department than the hospital has capacity to cope with, this is why currently the government are throwing money at hospitals to help manage the demand on beds which always goes up this time of year,
Declaring a major incident allows them to invoke a set of procedures which allows them to free up more beds in the hospital and involve more resources to deal with and manage the situation, it's the same sort of situation they would invoke if there had been a major incident such as a train or plan crash with huge numbers of casualties to deal with. It means they can redirect patients to other hospitals as facilities and call in agencies to help clear beds quicker, it also allows them to make press requests to the public to only attend accident and emergency if it's a genuine accident or emergency, for all those folk who like to turn up with a cold or minor injury a gp or walking centre could deal with.
Normally if a hospital declared a major incident because they had bed flow issues there would be hell to pay, however in this case it looks like they've been cheeky and used the CQC inspection to back up the case that the hospital is at capacity and this has helped enforce the need for a majax, this isn't something that the CQC has made them do.