[mlir][tosa] Add integer bitwidth conversion pass (#232853)
Add tosa-convert-integer-types-bitwidth to convert i4 to i8 and/or i48
to i64. This is useful to facilitate lowering to backends that do not
support i4 and/or i48.
Add a host byte-order lit feature to gate tests with little-endian
resource data.
Assisted-by: Codex