[PATCH] RISC-V: Zicbo{m,p,z} adjustments to riscv_multi_subset_supports_ext()

[Jan Beulich]

The lack thereof did caused gas to issue "internal: unreachable
INSN_CLASS_*" errors when trying to assemble respective insns without
the feature(s) enabled via e.g. ".option arch, ...". Of course a proper
hint towards the missing extension then wasn't given either.

--- a/bfd/elfxx-riscv.c
+++ b/bfd/elfxx-riscv.c
@@ -2440,6 +2440,12 @@ riscv_multi_subset_supports_ext (riscv_p
     {
     case INSN_CLASS_I:
       return "i";
+    case INSN_CLASS_ZICBOM:
+      return "zicbom";
+    case INSN_CLASS_ZICBOP:
+      return "zicbop";
+    case INSN_CLASS_ZICBOZ:
+      return "zicboz";
     case INSN_CLASS_ZICSR:
       return "zicsr";
     case INSN_CLASS_ZIFENCEI: