[fix test] Move typedefs-with-same-name.test into ARM folder (#167005)
https://github.com/llvm/llvm-project/pull/166767 mistakenly put the test
file outside the ARM folder, causing build bots that only have an x86
target to fail. Moving it into the ARM folder.
```
royshi-mac-home ~/public_llvm/build % bin/llvm-lit \
../llvm-project/llvm/test/tools/dsymutil/ARM/typedefs-with-same-name.test \
../llvm-project/llvm/test/tools/dsymutil/X86/DWARFLinkerParallel/odr-fwd-declaration.test
-- Testing: 2 tests, 2 workers --
PASS: LLVM :: tools/dsymutil/ARM/typedefs-with-same-name.test (1 of 2)
PASS: LLVM :: tools/dsymutil/X86/DWARFLinkerParallel/odr-fwd-declaration.test (2 of 2)
Testing Time: 0.23s
Total Discovered Tests: 2
Passed: 2 (100.00%)
```