Fix platform-specific client libraries for Linux

Do not hardcode library names, detect and depend on them properly instead.

Author: AMDmi3

CMakeLists.txt

@@ -389,7 +389,10 @@ elseif(TARGET_OS STREQUAL "mac")
   set(PLATFORM_LIBS ${CARBON})
 else()
   set(PLATFORM_CLIENT)
-  set(PLATFORM_CLIENT_LIBS GL GLU X11)
+  find_package(OpenGL)
+  find_package(X11)
+  set(PLATFORM_CLIENT_LIBS ${OPENGL_gl_LIBRARY} ${OPENGL_glu_LIBRARY} ${X11_X11_LIB})
+  set(PLATFORM_CLIENT_INCLUDE_DIRS ${OPENGL_INCLUDE_DIR} ${X11_X11_INCLUDE_PATH})
   if(TARGET_OS STREQUAL "linux")
     set(PLATFORM_LIBS rt) # clock_gettime for glibc < 2.17
   else()