doc: fix interactive commands in testpmd guide

doc: fix interactive commands in testpmd guide

Added some missing documentation for interactive mode commands

Fixes: 01b2092a5e4b ("testpmd: add dump commands for debug")
Fixes: caf05a1b8608 ("app/testpmd: new command to dump log types")
Fixes: 0f62d63593ed ("app/testpmd: support tunneled TSO in checksum engine")
Fixes: 8fff667578a7 ("app/testpmd: new command to add/remove multicast MAC addresses")
Fixes: ae03d0d18adf ("app/testpmd: command to configure MTU")
Fixes: f79959ea1504 ("app/testpmd: allow to configure RSS hash key")
Fixes: caf05a1b8608 ("app/testpmd: new command to dump log types")
Cc: stable@dpdk.org
Signed-off-by: Agalya Babu RadhaKrishnan <agalyax.babu.radhakrishnan@intel.com>
Reviewed-by: Rami Rosen <ramirose@gmail.com>
Acked-by: Bernard Iremonger <bernard.iremonger@intel.com>