[libunwind] Avoid a warning in 32 bit builds. NFC.

The warning was introduced with the recently merged SPARCv9
support in 2b9554b8850192bdd86c02eb671de1d866df8d87.

The cast matches the existing surrounding cases.

Differential Revision: https://reviews.llvm.org/D119353

NOKEYCHECK=True
GitOrigin-RevId: dfa5ab7b2b510e68ca2b11b043898c192633c0f6
1 file changed
tree: cdec8e0369aa0667dbcce8d7c2bca440632bfc72
  1. cmake/
  2. docs/
  3. include/
  4. src/
  5. test/
  6. .clang-format
  7. CMakeLists.txt
  8. LICENSE.TXT