Add missing mock call expectations

[benoit-nexthop]

CmdShowRouteDetailsTest was complaing about some unexpected calls:

GMOCK WARNING:
Uninteresting mock function call - returning directly.
    Function call: getAllPortInfo(@0x7f8d0c000b10 {})
NOTE: You can safely ignore the above warning unless this call should 
not happen.  Do not suppress it by blindly adding an EXPECT_CALL() if 
you don't mean to enforce the call.  See 
https://github.com/google/googletest/blob/master/docs/gmock_cook_book.md#knowing-when-to-expect
for details.

GMOCK WARNING:
Uninteresting mock function call - returning directly.
    Function call: getAggregatePortTable(@0x7f8d04001120 {})
NOTE: You can safely ignore the above warning unless this call should not happen.  Do not suppress it by blindly adding an EXPECT_CALL() if you don't mean to enforce the call.  See https://github.com/google/googletest/blob/master/docs/gmock_cook_book.md#knowing-when-to-expect for details.

GMOCK WARNING:
Uninteresting mock function call - returning directly.
    Function call: getAllPortInfo(@0x7f8d2d100c20 {})
NOTE: You can safely ignore the above warning unless this call should not happen.  Do not suppress it by blindly adding an EXPECT_CALL() if you don't mean to enforce the call.  See https://github.com/google/googletest/blob/master/docs/gmock_cook_book.md#knowing-when-to-expect for details.