CMakeLists.txt: Remove extra parenthesis
CMakeLists.txt: Remove extra parenthesis

Fixes #333
akheron/jansson,akheron/jansson,AmesianX/jansson,bstarynk/jansson,markalanj/jansson,AmesianX/jansson,akheron/jansson,Mephistophiles/jansson,Mephistophiles/jansson,markalanj/jansson,bstarynk/jansson,bstarynk/jansson,markalanj/jansson