Fix memory leak in selftest::test_expansion_to_rtl

Fix memory leak in selftest::test_expansion_to_rtl

"make selftest-valgrind" shows:

187 bytes in 1 blocks are definitely lost in loss record 567 of 669
    at 0x4A081D4: calloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
    by 0x1F08260: xcalloc (xmalloc.c:162)
    by 0xB24F32: init_emit() (emit-rtl.c:5843)
    by 0xC10080: prepare_function_start() (function.c:4803)
    by 0xC10254: init_function_start(tree_node*) (function.c:4877)
    by 0x1CDF92A: selftest::test_expansion_to_rtl() (function-tests.c:595)
    by 0x1CE007C: selftest::function_tests_c_tests() (function-tests.c:676)
    by 0x1E010E7: selftest::run_tests() (selftest-run-tests.c:98)
    by 0x1062D1E: toplev::run_self_tests() (toplev.c:2225)
    by 0x1062F40: toplev::main(int, char**) (toplev.c:2303)
    by 0x1E5B90A: main (main.c:39)

The allocation in question is:

  crtl->emit.regno_pointer_align
    = XCNEWVEC (unsigned char, crtl->emit.regno_pointer_align_length);

This patch fixes this leak (and makes the output of
"make selftest-valgrind" clean) by calling free_after_compilation at the
end of the selftest in question.

gcc/ChangeLog:
	* function-tests.c (selftest::test_expansion_to_rtl): Call
	free_after_compilation.

From-SVN: r263339