[K20D50M] PinNames correction, UART pins definitions, GPIO IRQ speed up (as KLxx)
[K20D50M] K20D50M - correct target name
[K20D50M] GPIO IRQ - CLZ to get position in irq handler
Merge pull request #397 from 0xc0170/dev_k20d50m

[K20D50M] K20D5M -> K20D50M