HHow to use quadTimer to trigger SAR ADC for only Kinetis KM sub-family without PDB module

[#1]

The SAR-ADC of KM family supports using 4 triggering signals to trigger SAR-ADC, for the KM sub-family with PDB, it is okay to use PDB. But for the KM family without PDB module, it is difficult to generate  4 triggering signals to trigger SAR-ADC.

The DOC introduce how to use quadTimer to generate 4 sequential triggering signals to trigger SAR-ADC so taht the SAR-ADC can get 4 samples in one conversion.