EEPROM emulation using internal flash sector 1(0x0800 4000 - 0x0800 7FFF) 16K, 2(0x0800 8000 - 0x0800 BFFF) 16K, 3(0x0800 C000 - 0x0800 FFFF) 16K.

Signed-off-by: cctsao1008 <chiacheng.tsao@gmail.com>