CMake: don't link sdlew when WITH_SDL=OFF

This caused a build error building Blender as a Python module
with !125556 applied.

extern/CMakeLists.txt

@@ -85,8 +85,10 @@ if(WITH_GTESTS)
   add_subdirectory(gmock)
 endif()
 
-if(WITH_SDL AND WITH_SDL_DYNLOAD)
-  add_subdirectory(sdlew)
+if(WITH_SDL)
+  if(WITH_SDL_DYNLOAD)
+    add_subdirectory(sdlew)
+  endif()
 endif()
 
 if(WITH_AUDASPACE AND NOT WITH_SYSTEM_AUDASPACE)

intern/audaspace/CMakeLists.txt

@@ -28,10 +28,12 @@ if(NOT WITH_SYSTEM_AUDASPACE)
   list(APPEND LIB
     audaspace
   )
-  if(WITH_SDL_DYNLOAD)
-    list(APPEND LIB
-      extern_sdlew
-    )
+  if(WITH_SDL)
+    if(WITH_SDL_DYNLOAD)
+      list(APPEND LIB
+        extern_sdlew
+      )
+    endif()
   endif()
 else()
   list(APPEND LIB

source/blender/python/intern/CMakeLists.txt

@@ -262,9 +262,13 @@ if(WITH_SDL)
     ${SDL_INCLUDE_DIR}
   )
   if(WITH_SDL_DYNLOAD)
+    list(APPEND INC
+      ../../../../extern/sdlew/include
+    )
     list(APPEND LIB
       extern_sdlew
     )
+    add_definitions(-DWITH_SDL_DYNLOAD)
   else()
     list(APPEND LIB
       ${SDL_LIBRARY}
@@ -273,13 +277,6 @@ if(WITH_SDL)
   add_definitions(-DWITH_SDL)
 endif()
 
-if(WITH_SDL_DYNLOAD)
-  list(APPEND INC
-    ../../../../extern/sdlew/include
-  )
-  add_definitions(-DWITH_SDL_DYNLOAD)
-endif()
-
 if(WITH_JACK)
   add_definitions(-DWITH_JACK)
 endif()