Fix misspellings in python marconiclient

Fix misspellings detected by:
* pip install misspellings
* git ls-files | grep -v locale | misspellings -f -

Change-Id: I4bbc0ba5be154950a160871ef5675039697f2314
Closes-Bug: #1257295
Merge "Fix misspellings in python marconiclient"