Frequency setting just after erase operation was causing some data
inconsistencies during write/read operations on some targets (frdm-k82f).
To fix this, frequency setting was moved before flash memory init.
- code refactoring and preparation for enabling DPI/QPI tests
- reduced multiple test count to 4
- use common flash config header for all MX25RXX35F chips
- fix sector erase max time on N25Q128A
Main idea of introduced changes is to ease adding support for new flash chips
Major changes:
- move implementation of all memory chip specific functions to memory config file (no weak functions)
- add support for 1-2-2 write