Remove unneeded dependency on X11

At least on FreeBSD, this is not needed.

Author: AMDmi3

CMakeLists.txt

@@ -25,14 +25,6 @@ IF(WINDOWS)
 ENDIF(WINDOWS)
 
 
-# X11 (for Linux/BSD only)
-
-IF(LINUX)
-FIND_PACKAGE(X11 REQUIRED)
-SET(ALL_LIBRARIES ${ALL_LIBRARIES} ${X11_LIBRARIES})
-ENDIF(LINUX)
-
-
 # libSDL2 (./share/cmake/FindSDL2.cmake)
 
 SET(CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/share/cmake)