cmake PnetCDF examples

Amber-MD/cpptraj cmake-cpptraj/SetupThirdParty.cmake :267 

find_package(PnetCDF)

NCAR/ParallelIO CMakeLists.txt :265 

find_package (PnetCDF COMPONENTS C Fortran)

merzlab/QUICK cmake/3rdPartyTools.cmake :410 

find_package(PnetCDF)