Revert partly "fixed function signature from openGetFile"

This reverts Cmake changes from commit 420e7616f54a1feefac8833c295cb0f62aca69cd.

daemon/CMakeLists.txt

@@ -9,9 +9,7 @@ project(ccats)
 # dependencies used by server and tests
 find_package(Threads REQUIRED)
 find_package(Boost 1.67 REQUIRED COMPONENTS system filesystem)
-find_package(PkgConfig REQUIRED)
-pkg_check_modules(JSONCPP jsoncpp)
-link_libraries(${JSONCPP_LIBRARIES})
+find_package(Jsoncpp REQUIRED)
 
 include(src/CMakeLists.txt)