[MLIR][Bytecode] Use consistent types for resolveEntry (#171502)

uint64_t and size_t are not the same across all platforms. This was
causing build failures when building this file for wasm:

llvm-project/mlir/lib/Bytecode/Reader/BytecodeReader.cpp:1323:19: error:
out-of-line definition of 'resolveEntry' does not match any declaration
in '(anonymous namespace)::AttrTypeReader'
1323 | T AttrTypeReader::resolveEntry(SmallVectorImpl<Entry<T>>
&entries, size_t index,
      |                   ^~~~~~~~~~~~

third_party/llvm/llvm-project/mlir/lib/Bytecode/Reader/BytecodeReader.cpp:851:7:
note: AttrTypeReader defined here
  851 | class AttrTypeReader {
      |       ^~~~~~~~~~~~~~
1 error generated.

Use uint64_t everywhere to ensure portability.

0 files changed, 0 insertions, 0 deletions