Remove special makefile rules / .sh files for some localedata tests.

The localedata tests tst-mbswcs and tst-wctype use custom .sh scripts
and makefile rules, but have no need to do so.  tst-mbswcs.sh runs a
series of test programs in succession (and nothing special is done
with the output of the programs); this patch makes the separate tests
into ordinary tests run directly by the usual makefile rules.
tst-wctype.sh runs one test with an environment variable and input
redirection; generic makefile rules also cover that, so again this
patch converts it into an ordinary test.  (The makefile dependency of
tst-wctype.out on sort-test.out that this patch removes appears to be
a cut-and-paste error; the test does not appear to use that file.
There is already a generic dependency of ordinary tests in this
directory on $(addprefix $(objpfx),$(CTYPE_FILES)).)

Tested x86_64.

localedata/ChangeLog:
	* Makefile (test-srcs): Remove tst-mbswcs1, tst-mbswcs2,
	tst-mbswcs3, tst-mbswcs4, tst-mbswcs5 and tst-wctype.
	(generated): Remove tst-mbswcs.out.
	(tests): Add tst-mbswcs1, tst-mbswcs2, tst-mbswcs3, tst-mbswcs4,
	tst-mbswcs5 and tst-wctype.
	(tests-special): Remove $(objpfx)tst-mbswcs.out and
	$(objpfx)tst-wctype.out.
	($(objpfx)tst-mbswcs.out): Remove rule.
	($(objpfx)tst-wctype.out): Likewise.
	(tst-wctype-ENV): New variable.
	* tst-mbswcs.sh: Remove file.
	* tst-wctype.sh: Likewise.