RISC-V: Add Privileged Architecture 1.13 CSRs.

This patch support RISC-V Privileged Architecture 1.13 CSRs 'medelegh' and
'hedelegh'. More details between 1.12 and 1.13 see [1].

[1] https://github.com/riscv/riscv-isa-manual/blob/main/src/priv-preface.adoc

Version log: Remove gas/po changes.

bfd/ChangeLog:

        * cpu-riscv.c: New option.
        * cpu-riscv.h (enum riscv_spec_class): Ditto.

binutils/ChangeLog:

        * doc/binutils.texi: New option.

gas/ChangeLog:

        * NEWS: Add priv-1.13 support.
        * config/tc-riscv.c: New option.
        * configure: Ditto.
        * configure.ac: Ditto.
        * testsuite/gas/riscv/csr-version-1p10.d: New CSR.
        * testsuite/gas/riscv/csr-version-1p10.l: New warning.
        * testsuite/gas/riscv/csr-version-1p11.d: New CSR.
        * testsuite/gas/riscv/csr-version-1p11.l: New warning.
        * testsuite/gas/riscv/csr-version-1p12.d: New CSR.
        * testsuite/gas/riscv/csr-version-1p12.l: New warning.
        * testsuite/gas/riscv/csr.s: New CSR.
        * testsuite/gas/riscv/attribute-15.d: New test.
        * testsuite/gas/riscv/attribute-16.d: New test.
        * testsuite/gas/riscv/csr-version-1p13.d: New test.
        * testsuite/gas/riscv/csr-version-1p13.l: New test.

include/ChangeLog:

        * opcode/riscv-opc.h (CSR_MEDELEGH): New CSR.
        (CSR_HEDELEGH): Ditto.
        (DECLARE_CSR): Ditto.
19 files changed