Rollup merge of #131174 - madsmtm:target-info-sparc-abi, r=pnkfelix

Fix `target_abi` in `sparc-unknown-none-elf`

This was previously set to `target_abi = "elf"`, but `elf` is not used elsewhere as a target ABI (even though there's many targets that have it in their name), so I've removed it.

CC target maintainer ``@jonathanpallant,`` what do you think about this?
``@rustbot`` label O-SPARC

compiler/rustc_target/src/spec/targets/sparc_unknown_none_elf.rs

@@ -7,7 +7,6 @@ pub(crate) fn target() -> Target {
         linker: Some("sparc-elf-gcc".into()),
         endian: Endian::Big,
         cpu: "v7".into(),
-        abi: "elf".into(),
         max_atomic_width: Some(32),
         atomic_cas: true,
         panic_strategy: PanicStrategy::Abort,