add LoongArch NCG support to 9.8

Hardware: Loongson-3C5000
Software: gcc-14.2.0-12, binutils-2.43.50.20241230

    9685 total tests, which gave rise to
   46953 test cases, of which
   37177 were skipped
       7 had missing libraries

    9617 expected passes
     121 expected failures

       0 caused framework failures
       0 caused framework warnings
       0 unexpected passes
       5 unexpected failures
       0 unexpected stat failures
      33 fragile tests

Unexpected failures:
   /tmp/ghctest-uclqur7c/test   spaces/testsuite/tests/rts/divbyzero.run                                 divbyzero [bad exit code (0)] (normal)
   /tmp/ghctest-uclqur7c/test   spaces/testsuite/tests/concurrent/should_run/hs_try_putmvar001.run       hs_try_putmvar001 [exit code non-0] (threaded1)
   /tmp/ghctest-uclqur7c/test   spaces/testsuite/tests/rts/pause-resume/list_threads_and_misc_roots.run  list_threads_and_misc_roots [exit code non-0] (threaded1)
   /tmp/ghctest-uclqur7c/test   spaces/testsuite/tests/profiling/should_run/T11489.run                   T11489 [bad stderr] (normal)
   /tmp/ghctest-uclqur7c/test   spaces/testsuite/tests/rts/testwsdeque.run                               testwsdeque [exit code non-0] (threaded1)