seL4: prefix LLVM's tools with supported seL4 target triples

Mainly to get binutils symlinked as expected by the seL4's
cmake build system.

pycheribuild/projects/cross/llvm.py

@@ -39,6 +39,8 @@
 from ...config.compilation_targets import (
  CheriBSDMorelloTargetInfo,
  CheriBSDTargetInfo,
+ Sel4TargetInfo,
+ Sel4MorelloTargetInfo,
  CompilationTargets,
  FreeBSDTargetInfo,
 )
@@ -547,6 +549,8 @@ def triple_prefixes_for_binaries(self) -> "Iterable[str]":
  include_version=False),
  CheriBSDTargetInfo.triple_for_target(CompilationTargets.CHERIBSD_X86_64, self.config,
  include_version=False),
+ Sel4TargetInfo.triple_for_target(CompilationTargets.SEL4_RISCV64, self.config,
+ include_version=False),
  ]
  return [x + "-" for x in triples]
 
@@ -576,6 +580,8 @@ def triple_prefixes_for_binaries(self) -> "Iterable[str]":
  triples = [
  CheriBSDMorelloTargetInfo.triple_for_target(CompilationTargets.CHERIBSD_MORELLO_PURECAP, self.config,
  include_version=False),
+ Sel4TargetInfo.triple_for_target(CompilationTargets.SEL4_MORELLO_NO_CHERI, self.config,
+ include_version=False),
  ]
  return [x + "-" for x in triples]