Add cmake test to find xf86vmode.h -- which would live in the X includes dir, but I don't know how to get that directory from earlier checks, so look in likely places instead. Code based on FindSane.cmake. License of this 'code' is BSD.

svn path=/trunk/KDE/kdegraphics/cmake/modules/; revision=590778

cmake/modules/FindXVidModeExtensions.cmake

@@ -0,0 +1,18 @@
+# cmake macro to test if we have xvidmode extensions - xf86
+#
+#  XVIDMODEEXTENSIONS_FOUND - system has XVIDMODEEXTENSIONS libs
+
+FIND_PATH(XVIDMODEEXTENSIONS_INCLUDE_DIR X11/extensions/xf86vmode.h
+   /usr/include
+   /usr/local/include
+   /usr/X11R6/include
+)
+
+if (XVIDMODEEXTENSIONS_INCLUDE_DIR)
+   set(XVIDMODEEXTENSIONS_FOUND TRUE)
+   message(STATUS "Found X VidMode extensions: ${XVIDMODEEXTENSIONS_INCLUDE_DIR}")
+else (XVIDMODEEXTENSIONS_INCLUDE_DIR)
+   set(XVIDMODEEXTENSIONS_FOUND FALSE)
+   message(STATUS "Did not find X VidMode extensions")
+endif (XVIDMODEEXTENSIONS_INCLUDE_DIR)
+