Cleanup proj version detection (#46134)

Make sure the proj version detection logic is made available to reverse dependencies too.
In short, move it from an obscure define in a custom cmake find file to a generated header.

Co-authored-by: Mathieu Pellerin <nirvn.asia@gmail.com>

cmake/FindProj.cmake

@@ -86,7 +86,6 @@ IF (PROJ_FOUND)
    ENDIF (NOT PROJ_FIND_QUIETLY)
 
    INCLUDE_DIRECTORIES(BEFORE SYSTEM ${PROJ_INCLUDE_DIR})
-   ADD_DEFINITIONS(-DPROJ_VERSION_MAJOR=${PROJ_VERSION_MAJOR})
 
 ELSE (PROJ_FOUND)
 

cmake_templates/qgsconfig.h.in

@@ -51,6 +51,10 @@
 #define PYTHON_VERSION_MINOR "${Python_VERSION_MINOR}"
 #define PYTHON_VERSION_PATCH "${Python_VERSION_PATCH}"
 
+#define PROJ_VERSION_MAJOR ${PROJ_VERSION_MAJOR}
+#define PROJ_VERSION_MINOR ${PROJ_VERSION_MINOR}
+#define PROJ_VERSION_PATCH ${PROJ_VERSION_PATCH}
+
 #cmakedefine USING_NMAKE
 
 #cmakedefine USING_NINJA

src/core/proj/qgscoordinatereferencesystem.h

@@ -32,6 +32,7 @@
 
 //qgis includes
 #include "qgis_sip.h"
+#include "qgsconfig.h"
 #include "qgsunittypes.h"
 #include "qgsrectangle.h"
 #include "qgssqliteutils.h"