[llvm] [BinaryFormat] Adjust OSABI functions and add unittests (PR #90270)

[James Henderson via llvm-commits]

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@@ -1939,11 +1939,12 @@ uint16_t convertArchNameToEMachine(StringRef Arch);
 /// Convert an ELF's e_machine value into an architecture name.
 StringRef convertEMachineToArchName(uint16_t EMachine);
 
-/// Convert a OS into ELF's EI_OSABI value.
-uint8_t convertOSToOSAbi(StringRef OS);
+// Convert a lowercase string identifier into an OSABI value.
+uint8_t convertNameToOSAbi(StringRef Name);
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jh7370 wrote:

Nit: whilst changing the signature, now might be a good time to fix the casing of `Abi` to `ABI`, since it's an acronym and therefore should be all uppercase. Same below, including the parameter.

https://github.com/llvm/llvm-project/pull/90270