remove sdl1 from cmake files

CMakeLists.txt

@@ -21,7 +21,6 @@ option(ENABLE_EDITOR "Enable compilation of map editor" OFF)
 option(ENABLE_LAUNCHER "Enable compilation of launcher" ON)
 option(ENABLE_TEST "Enable compilation of unit tests" OFF)
 option(ENABLE_PCH "Enable compilation using precompiled headers" ON)
-option(ENABLE_SDL2 "Use SDL2 for compilation instead of SDL 1.2" ON)
 
 ############################################
 #        Building section                  #
@@ -118,26 +117,20 @@ if (MINIZIP_FOUND)
     add_definitions(-DUSE_SYSTEM_MINIZIP)
 endif()
 
-if (ENABLE_SDL2)
-	find_package(SDL2 REQUIRED)
-	find_package(SDL2_image REQUIRED)
-	find_package(SDL2_mixer REQUIRED)
-	find_package(SDL2_ttf REQUIRED)
-
-	set(SDL_INCLUDE_DIR "${SDL2_INCLUDE_DIR}")
-	set(SDLTTF_INCLUDE_DIR "${SDL2_TTF_INCLUDE_DIR}")
-	set(SDLIMAGE_INCLUDE_DIR "${SDL2_IMAGE_INCLUDE_DIR}")
-	set(SDLMIXER_INCLUDE_DIR "${SDL2_MIXER_INCLUDE_DIR}")
-	set(SDL_LIBRARY "${SDL2_LIBRARY}")
-	set(SDLTTF_LIBRARY "${SDL2_TTF_LIBRARY}")
-	set(SDLIMAGE_LIBRARY "${SDL2_IMAGE_LIBRARY}")
-	set(SDLMIXER_LIBRARY "${SDL2_MIXER_LIBRARY}")
-else()
-	find_package(SDL REQUIRED)
-	find_package(SDL_image REQUIRED)
-	find_package(SDL_mixer REQUIRED)
-	find_package(SDL_ttf REQUIRED)
-endif()
+find_package(SDL2 REQUIRED)
+find_package(SDL2_image REQUIRED)
+find_package(SDL2_mixer REQUIRED)
+find_package(SDL2_ttf REQUIRED)
+
+set(SDL_INCLUDE_DIR "${SDL2_INCLUDE_DIR}")
+set(SDLTTF_INCLUDE_DIR "${SDL2_TTF_INCLUDE_DIR}")
+set(SDLIMAGE_INCLUDE_DIR "${SDL2_IMAGE_INCLUDE_DIR}")
+set(SDLMIXER_INCLUDE_DIR "${SDL2_MIXER_INCLUDE_DIR}")
+set(SDL_LIBRARY "${SDL2_LIBRARY}")
+set(SDLTTF_LIBRARY "${SDL2_TTF_LIBRARY}")
+set(SDLIMAGE_LIBRARY "${SDL2_IMAGE_LIBRARY}")
+set(SDLMIXER_LIBRARY "${SDL2_MIXER_LIBRARY}")
+
 include(cotire)
 
 if (ENABLE_EDITOR OR ENABLE_LAUNCHER)