This patch enables perf jitdump for riscv64 and was tested with V8 on
qemu rv64.

Qemu rv64:

  $ perf record -e cpu-clock -c 1000 -g -k mono ./d8_rv64 --perf-prof --no-write-protect-code-memory test.js
  $ perf inject -j -i perf.data -o perf.data.jitted
  $ perf report -i perf.data.jitted

Output:

  To display the perf.data header info, please use --header/--header-only options.

  Total Lost Samples: 0

  Samples: 87K of event 'cpu-clock'
  Event count (approx.): 87974000

  Children  Self   Command   Shared Object      Symbol

  ....
   0.28%    0.06%  d8_rv64   d8_rv64            [.] _ZN2v88internal6WasmJs7InstallEPNS0_7IsolateEb
   0.28%    0.00%  d8_rv64   d8_rv64            [.] _ZN2v88internal10ParserBaseINS0_6ParserEE22ParseLogicalExpressionEv
   0.28%    0.03%  d8_rv64   jitted-112-76.so   [.] Builtin:InterpreterEntryTrampoline
   0.12%    0.00%  d8_rv64   d8_rv64            [.] _ZN2v88internal19ContextDeserializer11DeserializeEPNS0_7IsolateENS0_6HandleINS0_13JSGlobalProxyEEENS_33DeserializeInternalFieldsCallbackE
   0.12%    0.01%  d8_rv64   jitted-112-651.so  [.] Builtin:CEntry_Return1_DontSaveFPRegs_ArgvOnStack_NoBuiltinExit
  ....
Signed-off-by: Eric Lin <eric.lin@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: greentime.hu@sifive.com
Cc: linux-riscv@lists.infradead.org
Link: http://lore.kernel.org/lkml/20220406142606.18464-2-eric.lin@sifive.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>