Some recently added libstdc++ filesystem tests are missing a
dg-require-filesystem-ts.

Committed as obvious.

    libstdc++/testsuite/
	* 27_io/filesystem/operations/all.cc: Add dg-require-filesystem-ts.
	* 27_io/filesystem/operations/resize_file.cc: Likewise.
	* 27_io/filesystem/path/generation/normal2.cc: Likewise.

From-SVN: r268989