v1.32+change_storage: Add the capability to change the storage (eMMC, SD, SPINOR...).

Implemented by reverse engineering of windows RKDevTool USB transactions.
The naming of operations (eg. READ_STORAGE, CHANGE_STORAGE) are
pure speculation, but the result is effective.
Also, the numbering of storage device (eg. 1=eMMC, 2=SD, 9=SPINOR) may be
dependent of the SOC.

Developed and tested on rk3588 (Radxa Rock 5 ITX)

Example of usage:
  rkdeveloptool db rk3588_spl_loader_v1.15.113.bin
  # select the SPINOR
  rkdeveloptool cs 9
  # clear the whole SPINOR device
  rkdeveloptool ef

  # write an image starting at block 0
  rkdeveloptool wl 0 /tmp/spinor_image.bin