Rollup merge of rust-lang#136830 - RalfJung:hurd-x87-footnote, r=Noratrieb

fix i686-unknown-hurd-gnu x87 footnote

I missed this in rust-lang#136700.

r? ``@Noratrieb``

Author: jhpratt

src/doc/rustc/src/platform-support.md

@@ -313,7 +313,7 @@ target | std | host | notes
 [`i586-unknown-netbsd`](platform-support/netbsd.md) | ✓ |  | 32-bit x86 (original Pentium) [^x86_32-floats-x87]
 [`i686-apple-darwin`](platform-support/apple-darwin.md) | ✓ | ✓ | 32-bit macOS (10.12+, Sierra+, Penryn) [^x86_32-floats-return-ABI]
 `i686-unknown-haiku` | ✓ | ✓ | 32-bit Haiku (Pentium 4) [^x86_32-floats-return-ABI]
-[`i686-unknown-hurd-gnu`](platform-support/hurd.md) | ✓ | ✓ | 32-bit GNU/Hurd (Pentium 4) [^x86_32-floats-x87]
+[`i686-unknown-hurd-gnu`](platform-support/hurd.md) | ✓ | ✓ | 32-bit GNU/Hurd (Pentium 4) [^x86_32-floats-return-ABI]
 [`i686-unknown-netbsd`](platform-support/netbsd.md) | ✓ | ✓ | NetBSD/i386 (Pentium 4) [^x86_32-floats-return-ABI]
 [`i686-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | 32-bit OpenBSD (Pentium 4) [^x86_32-floats-return-ABI]
 [`i686-unknown-redox`](platform-support/redox.md) | ✓ |  | i686 Redox OS (PentiumPro) [^x86_32-floats-x87]