examples/mi-mctp: Add Get Log Page example

examples/mi-mctp: Add Get Log Page example

Since we now have the Get Log Page API, add an example to the mi-mctp
utility. This will dump the log page data as hex:

  # mi-mctp 1 9 get-log-page 1
  Get log page (log id = 0x01) data:
  00000000  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  |................|
  00000010  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  |................|
  00000020  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  |................|
  [...]

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>