fix armv7a-none-eabihf tier doc

Author: cezarbbb

src/doc/rustc/src/platform-support/arm-none-eabi.md

@@ -12,7 +12,7 @@ their own document.
 ### Tier 2 Target List
 
 - Arm A-Profile Architectures
-  - [`armv7a-none-eabi`](armv7a-none-eabi.md)
+  - [`armv7a-none-eabi` and `armv7a-none-eabihf`](armv7a-none-eabi.md)
   - [`thumbv7a-none-eabi` and `thumbv7a-none-eabihf`](armv7a-none-eabi.md)
 - Arm R-Profile Architectures
   - [`armv7r-none-eabi` and `armv7r-none-eabihf`](armv7r-none-eabi.md)
@@ -32,7 +32,7 @@ their own document.
 ### Tier 3 Target List
 
 - Arm A-Profile Architectures
-  - [`armv7a-none-eabihf`](armv7a-none-eabi.md)
+  - None
 - Arm R-Profile Architectures
   - None
 - Arm M-Profile Architectures