Add deprecation note to legacy makefiles in code.

git-svn-id: https://assimp.svn.sourceforge.net/svnroot/assimp/trunk@698 67173fc5-114c-0410-ac8e-9d2fd5bffc1f

code/makefile

@@ -1,3 +1,6 @@
+### USE OF THIS MAKEFILE IS NOT RECOMMENDED.
+### It is no longer maintained. Use CMAKE instead.
+
 # Makefile for Open Asset Import Library (GNU-make)
 # [email protected]
 

code/makefile.mingw

@@ -1,3 +1,5 @@
+### USE OF THIS MAKEFILE IS NOT RECOMMENDED.
+### It is no longer maintained. Use CMAKE instead.
 
 # ---------------------------------------------------------------------------
 # Makefile for Open Asset Import Library (MinGW32-make)