[NDS32] Implement e8 pipeline.
gcc/
* config.gcc (nds32*-*-*): Check that e8 is valid to --with-cpu.
* config/nds32/nds32-e8.md: New file.
* config/nds32/nds32-opts.h (nds32-cpu_type): Add CPU_E8.
* config/nds32/nds32-pipelines-auxiliary.c: Implementation for e8
pipeline.
* config/nds32/nds32-protos.h: More declarations for e8 pipeline.
* config/nds32/nds32.md (pipeline_model): Add e8.
* config/nds32/nds32.opt (mcpu): Support e8 pipeline cpus.
* config/nds32/pipelines.md: Include e8 settings.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@259220 138bc75d-0d04-0410-961f-82ee72b054a4