x86-64: Fix art_quick_osr_stub for unwinder.

Test: testrunner.py --host --jit --64 570-checker-osr
Test: Run the above test under gdb, break in the stub and
      manually check that "bt 3" works correctly at every
      instruction and "bt 4" works in called methods if we
      also pass -Xcompiler-option --generate-debug-info.
Bug: 73954823

Change-Id: I7352febb0c4c0414648e2b825511b83d9bcc268a