PHILADELPHIA — Before Tyrese Maxey’s 51-point dazzler at the Utah Jazz, a disastrous 76ers road trip had been defined by Joel Embiid’s knee issues. The aggravation in Indianapolis. The late scratch — and ensuing controversy — in Denver. The hobbled attempt to return to action at Golden State, punctuated by the unfortunate blow of the Golden State Warriors’ Jonathan Kuminga falling on top of his left leg. Embiid has now been officially diagnosed with a lateral meniscus injury, which will keep him out at least through the weekend while a treatment plan is finalized. His chances to repeat as MVP …