[Add devtools regs and mii_mgr]

[Description]
Add devtools regs and mii_mgr
1. regs tool for debug
2. mii_mgr tool for detecting wan link up when external 2.5G phy in force mode

[Release-log]

7 files changed
tree: 10731b21b5fe42538742c51f3299032fccbb6317
  1. classes/
  2. conf/
  3. recipes-connectivity/
  4. recipes-devtools/
  5. recipes-kernel/