Remove unreachable code in prvSelectHighestPriorityTask

[chinglee-iot]

Description

• There should be at least idle task ready to run. Previous configASSERT ensure this function is called when scheduler is running.

configASSERT( xSchedulerRunning == pdTRUE );

• The same reason xTaskScheduled is always true when leaving the while loop.
• xLowestPriorityCore can't be greater than configNUMBER_OF_CORES due to the loop implementation.

Test Steps

Related Issue

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