re PR testsuite/35647 (FAIL: gcc.dg/cpp/cmdlne-d(I|M)-M.c scan-file (^|\\n)cmdlne-d(I|M)-M[^\\n]*:[^\\n]*cmdlne-d(I|M)-M.c)

PR testsuite/35647
* gcc.dg/cpp/cmdlne-dI-M.c: Match optional continuation.
* gcc.dg/cpp/cmdlne-dM-M.c: Likewise.
* gcc.dg/cpp/cmdlne-dN-M.c: Match correct file name and optional
continuation and remove xfail.

From-SVN: r133373