Try finding NetCDF built with cmake or pkg-config

I found taking advantage of pkg-config useful on Ciclad, because we
already have to play with pkg-config to find NetCDF-Fortran.

FindNetCDF.cmake

+# https://gitlab.kitware.com/vtk/vtk/blob/d42d8eb02bc965134eb92dde4aaab92223cb8a6a/CMake/FindNetCDF.cmake
+
+# I have had trouble with this version of FindNetCDF for ml2pl on
+# Irene, but, on the other hand, I found this version of FindNetCDF
+# useful for NetCDF95 on Ciclad, taking advantage of pkg-config.
+
+#[==[
+Provides the following variables:
+
+  * `NetCDF_FOUND`: Whether NetCDF was found or not.
+  * `NetCDF_INCLUDE_DIRS`: Include directories necessary to use NetCDF.
+  * `NetCDF_LIBRARIES`: Libraries necessary to use NetCDF.
+  * `NetCDF_VERSION`: The version of NetCDF found.
+  * `NetCDF::NetCDF`: A target to use with `target_link_libraries`.
+#]==]
+
+# Try to find a CMake-built NetCDF.
+find_package(netCDF CONFIG QUIET)
+if (netCDF_FOUND)
+  # Forward the variables in a consistent way.
+  set(NetCDF_FOUND "${netCDF_FOUND}")
+  set(NetCDF_INCLUDE_DIRS "${netCDF_INCLUDE_DIR}")
+  set(NetCDF_LIBRARIES "${netCDF_LIBRARIES}")
+  set(NetCDF_VERSION "${NetCDFVersion}")
+  if (NOT TARGET NetCDF::NetCDF)
+    add_library(NetCDF::NetCDF INTERFACE IMPORTED)
+    set_target_properties(NetCDF::NetCDF PROPERTIES
+      INTERFACE_LINK_LIBRARIES "${NetCDF_LIBRARIES}")
+  endif ()
+  # Skip the rest of the logic in this file.
+  return ()
+endif ()
+
+find_package(PkgConfig QUIET)
+if (PkgConfig_FOUND)
+  pkg_check_modules(_NetCDF QUIET netcdf IMPORTED_TARGET)
+  if (_NetCDF_FOUND)
+    # Forward the variables in a consistent way.
+    set(NetCDF_FOUND "${_NetCDF_FOUND}")
+    set(NetCDF_INCLUDE_DIRS "${_NetCDF_INCLUDE_DIRS}")
+    set(NetCDF_LIBRARIES "${_NetCDF_LIBRARIES}")
+    set(NetCDF_VERSION "${_NetCDF_VERSION}")
+    if (NOT TARGET NetCDF::NetCDF)
+      add_library(NetCDF::NetCDF INTERFACE IMPORTED)
+      set_target_properties(NetCDF::NetCDF PROPERTIES
+        INTERFACE_LINK_LIBRARIES "PkgConfig::_NetCDF")
+    endif ()
+    # Skip the rest of the logic in this file.
+    return ()
+  endif ()
+endif ()
+
 find_path(NetCDF_INCLUDE_DIR
   NAMES netcdf.h
   DOC "netcdf include directories")