CMake: Align sources and headers in two columns

src/CMakeLists.txt

@@ -40,11 +40,14 @@ add_library( exiv2lib_int OBJECT
 )
 
 add_library( exiv2lib 
+    ../include/exiv2/config.h
+    ../include/exiv2/exiv2.hpp
+    ../include/exiv2/rwlock.hpp
+    ../include/exiv2/slice.hpp
     asfvideo.cpp            ../include/exiv2/asfvideo.hpp
     basicio.cpp             ../include/exiv2/basicio.hpp
     bigtiffimage.cpp
     bmpimage.cpp            ../include/exiv2/bmpimage.hpp
-    ../include/exiv2/config.h
     convert.cpp             ../include/exiv2/convert.hpp
     cr2image.cpp            ../include/exiv2/cr2image.hpp
     crwimage.cpp            ../include/exiv2/crwimage.hpp
@@ -53,7 +56,6 @@ add_library( exiv2lib
     epsimage.cpp            ../include/exiv2/epsimage.hpp
     error.cpp               ../include/exiv2/error.hpp
     exif.cpp                ../include/exiv2/exif.hpp
-    ../include/exiv2/exiv2.hpp
     futils.cpp              ../include/exiv2/futils.hpp
     gifimage.cpp            ../include/exiv2/gifimage.hpp
     http.cpp                ../include/exiv2/http.hpp
@@ -74,8 +76,6 @@ add_library( exiv2lib
     rafimage.cpp            ../include/exiv2/rafimage.hpp
     riffvideo.cpp           ../include/exiv2/riffvideo.hpp
     rw2image.cpp            ../include/exiv2/rw2image.hpp
-    ../include/exiv2/rwlock.hpp
-    ../include/exiv2/slice.hpp
     tags.cpp                ../include/exiv2/tags.hpp
     tgaimage.cpp            ../include/exiv2/tgaimage.hpp
     tiffimage.cpp           ../include/exiv2/tiffimage.hpp
@@ -86,7 +86,6 @@ add_library( exiv2lib
     webpimage.cpp           ../include/exiv2/webpimage.hpp
     xmp.cpp                 ../include/exiv2/xmp_exiv2.hpp
     xmpsidecar.cpp          ../include/exiv2/xmpsidecar.hpp
-
     $<TARGET_OBJECTS:exiv2lib_int>
 )