unix/linux: update to gcc 13.2.0, qemu 8.0.3 for loong64 and and Go 1.21.0 for all

Running `GOOS=linux GOARCH={amd64,arm64,loong64,mips64le,riscv64} ./mkall.sh`
produces no changes, as expected.

Update Loong64's cross toolchain to support for the ELF psABI v2.0 relocs [1].

Updates #58784.

[1]: https://loongson.github.io/LoongArch-Documentation/LoongArch-ELF-ABI-EN.html

Change-Id: I676893b934d8cfc30b9f3702fc92a5ab82f7f116
Reviewed-on: https://go-review.googlesource.com/c/sys/+/483455
Auto-Submit: Tobias Klauser <[email protected]>
Auto-Submit: Ian Lance Taylor <[email protected]>
Reviewed-by: Meidan Li <[email protected]>
Run-TryBot: Ian Lance Taylor <[email protected]>
Run-TryBot: Tobias Klauser <[email protected]>
Reviewed-by: Tobias Klauser <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Bryan Mills <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>

Author: abner-chenc

unix/linux/Dockerfile

@@ -21,9 +21,9 @@ RUN git clone --branch v6.4 --depth 1 https://kernel.googlesource.com/pub/scm/li
 RUN git clone --branch release/2.37/master --depth 1 https://sourceware.org/git/glibc.git
 
 # Get Go
-ENV GOLANG_VERSION 1.21rc2
+ENV GOLANG_VERSION 1.21.0
 ENV GOLANG_DOWNLOAD_URL https://golang.org/dl/go$GOLANG_VERSION.linux-amd64.tar.gz
-ENV GOLANG_DOWNLOAD_SHA256 8fe90332727c606019e80a7368e23f5e65ad59520e45ee4010692f15572e45c6
+ENV GOLANG_DOWNLOAD_SHA256 d0398903a16ba2232b389fb31032ddf57cac34efda306a0eebac34f0965a0742
 
 RUN curl -fsSL "$GOLANG_DOWNLOAD_URL" -o golang.tar.gz \
     && echo "$GOLANG_DOWNLOAD_SHA256  golang.tar.gz" | sha256sum -c - \
@@ -52,8 +52,8 @@ RUN apt-get update && apt-get install -y \
     && rm -rf /var/lib/apt/lists/*
 
 # Only for loong64, getting tools of qemu-user and gcc-cross-compiler
-ENV LOONG64_BASE_URL https://github.com/loongson/build-tools/releases/download/2022.09.06
-ENV LOONG64_GCC  loongarch64-clfs-6.3-cross-tools-gcc-glibc.tar.xz
+ENV LOONG64_BASE_URL https://github.com/loongson/build-tools/releases/download/2023.08.08
+ENV LOONG64_GCC  CLFS-loongarch64-8.1-x86_64-cross-tools-gcc-glibc.tar.xz
 ENV LOONG64_QEMU qemu-loongarch64
 ENV LOONG64_GCC_DOWNLOAD_URL  $LOONG64_BASE_URL/$LOONG64_GCC
 ENV LOONG64_QEMU_DOWNLOAD_URL $LOONG64_BASE_URL/$LOONG64_QEMU