cmake: Forgot to add this file to revision control.

Fixes Bugzilla #5003.

sdl2-config-version.cmake.in

@@ -0,0 +1,11 @@
+set(PACKAGE_VERSION "@SDL_VERSION@")
+
+if(PACKAGE_VERSION VERSION_LESS PACKAGE_FIND_VERSION)
+  set(PACKAGE_VERSION_COMPATIBLE FALSE)
+else()
+  set(PACKAGE_VERSION_COMPATIBLE TRUE)
+  if(PACKAGE_FIND_VERSION STREQUAL PACKAGE_VERSION)
+    set(PACKAGE_VERSION_EXACT TRUE)
+  endif()
+endif()
+