Rollup merge of rust-lang#118704 - esp-rs:rv32-tier-2, r=davidtwco

Promote `riscv32{im|imafc}` targets to tier 2

Pending the approval of [the MCP](rust-lang/compiler-team#701).

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

@@ -161,7 +161,9 @@ target | std | notes
 [`nvptx64-nvidia-cuda`](platform-support/nvptx64-nvidia-cuda.md) | * | --emit=asm generates PTX code that [runs on NVIDIA GPUs]
 [`riscv32imac-unknown-none-elf`](platform-support/riscv32imac-unknown-none-elf.md) | * | Bare RISC-V (RV32IMAC ISA)
 [`riscv32i-unknown-none-elf`](platform-support/riscv32imac-unknown-none-elf.md) | * | Bare RISC-V (RV32I ISA)
+[`riscv32im-unknown-none-elf`](platform-support/riscv32imac-unknown-none-elf.md) | * |  | Bare RISC-V (RV32IM ISA)
 [`riscv32imc-unknown-none-elf`](platform-support/riscv32imac-unknown-none-elf.md) | * | Bare RISC-V (RV32IMC ISA)
+[`riscv32imafc-unknown-none-elf`](platform-support/riscv32imac-unknown-none-elf.md) | * | Bare RISC-V (RV32IMAFC ISA)
 `riscv64gc-unknown-none-elf` | * | Bare RISC-V (RV64IMAFDC ISA)
 `riscv64imac-unknown-none-elf` | * | Bare RISC-V (RV64IMAC ISA)
 `sparc64-unknown-linux-gnu` | ✓ | SPARC Linux (kernel 4.4, glibc 2.23)
@@ -318,8 +320,6 @@ target | std | host | notes
 [`powerpc64-ibm-aix`](platform-support/aix.md) | ? |  | 64-bit AIX (7.2 and newer)
 `riscv32gc-unknown-linux-gnu` |   |   | RISC-V Linux (kernel 5.4, glibc 2.33)
 `riscv32gc-unknown-linux-musl` |   |   | RISC-V Linux (kernel 5.4, musl + RISCV32 support patches)
-[`riscv32imafc-unknown-none-elf`](platform-support/riscv32imac-unknown-none-elf.md) | * | Bare RISC-V (RV32IMAFC ISA)
-[`riscv32im-unknown-none-elf`](platform-support/riscv32imac-unknown-none-elf.md) | * |  | Bare RISC-V (RV32IM ISA)
 [`riscv32imac-unknown-xous-elf`](platform-support/riscv32imac-unknown-xous-elf.md) | ? |  | RISC-V Xous (RV32IMAC ISA)
 [`riscv32imc-esp-espidf`](platform-support/esp-idf.md) | ✓ |  | RISC-V ESP-IDF
 [`riscv32imac-esp-espidf`](platform-support/esp-idf.md) | ✓ |  | RISC-V ESP-IDF

src/doc/rustc/src/platform-support/riscv32imac-unknown-none-elf.md

@@ -1,6 +1,6 @@
 # `riscv32{i,im,imc,imac,imafc}-unknown-none-elf`
 
-**Tier: 2/3**
+**Tier: 2**
 
 Bare-metal target for RISC-V CPUs with the RV32I, RV32IM, RV32IMC, RV32IMAFC and RV32IMAC ISAs.
 
@@ -24,11 +24,11 @@ This target is included in Rust and can be installed via `rustup`.
 
 ## Testing
 
-This is a cross-compiled no-std target, which must be run either in a simulator
+This is a cross-compiled `no-std` target, which must be run either in a simulator
 or by programming them onto suitable hardware. It is not possible to run the
-Rust testsuite on this target.
+Rust test-suite on this target.
 
 ## Cross-compilation toolchains and C code
 
 This target supports C code. If interlinking with C or C++, you may need to use
-riscv64-unknown-elf-gcc as a linker instead of rust-lld.
+`riscv64-unknown-elf-gcc` as a linker instead of `rust-lld`.