* tests/test-mbstowcs1.sh: New file, based on tests/test-mbsrtowcs1.sh.
* tests/test-mbstowcs2.sh: New file, based on tests/test-mbsrtowcs2.sh.
* tests/test-mbstowcs3.sh: New file, based on tests/test-mbsrtowcs3.sh.
* tests/test-mbstowcs4.sh: New file, based on tests/test-mbsrtowcs4.sh.
* tests/test-mbstowcs5.sh: New file, based on tests/test-mbsrtowcs5.sh.
* tests/test-mbstowcs.c: New file, based on tests/test-mbsrtowcs.c.
* modules/mbstowcs-tests: New file, based on modules/mbsrtowcs-tests.