remove useless if-before-free tests

Change "if (E) free (E);" to "free (E);" everywhere except in the
libgo/, intl/, zlib/ and classpath/ directories.
Also transform equivalent variants like
"if (E != NULL) free (E);" and allow an extra cast on the
argument to free.  Otherwise, the tested and freed "E"
expressions must be identical, modulo white space.

From-SVN: r172785
diff --git a/libcpp/init.c b/libcpp/init.c
index 5c6dacf..5ba6666 100644
--- a/libcpp/init.c
+++ b/libcpp/init.c
@@ -259,8 +259,7 @@
   while (CPP_BUFFER (pfile) != NULL)
     _cpp_pop_buffer (pfile);
 
-  if (pfile->out.base)
-    free (pfile->out.base);
+  free (pfile->out.base);
 
   if (pfile->macro_buffer)
     {