Rollup merge of rust-lang#75634 - scileo:fix-75581, r=ehuss

Mark x86_64-linux-kernel as *

This should fix rust-lang#75581.

This is my first contribution to the Rust organization. Please, feel free to tell me if I did anything wrong :)

Author: JohnTitor

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

@@ -204,7 +204,7 @@ target | std | host | notes
 `thumbv4t-none-eabi` | * |  | ARMv4T T32
 `x86_64-apple-ios-macabi` | ✓[^apple] |  | Apple Catalyst
 `x86_64-apple-tvos` | *[^apple] | | x86 64-bit tvOS
-`x86_64-linux-kernel` | ? |  | Linux kernel modules
+`x86_64-linux-kernel` | * |  | Linux kernel modules
 `x86_64-pc-solaris` | ? |  |
 `x86_64-pc-windows-msvc` | ✓ |  | 64-bit Windows XP support
 `x86_64-unknown-cloudabi` | ✓ |  | 64-bit CloudABI