add proj to cmake

CMakeLists.txt

@@ -37,9 +37,13 @@ ELSE()
   message("wordexp.h is not found" )
 ENDIF()
 
+### -------------- proj ---------------------------
+find_package(PROJ)
+if(PROJ4::proj)
+  list(APPEND cdo_compile_defintions ${HAVE_PROJ})
+endif()
 
 ### -------------- fftw3 ---------------------------
-
 message("Start check for fftw3")
 find_package(FFTW3 3.0 REQUIRED)
 if(NOT FFTW3_LIBRARIES)