rustls: update rustls-ffi 0.10.0

This brings in version 0.21.0 of the upstream rustls implementation,
which notable includes support for IP address certificates.

Closes #10865

.github/workflows/linux.yml

@@ -264,7 +264,7 @@ jobs:
 
     - if: ${{ contains(matrix.build.install_steps, 'rustls') }}
       run: |
-        git clone --quiet --depth=1 -b v0.9.2 --recursive https://github.com/rustls/rustls-ffi.git
+        git clone --quiet --depth=1 -b v0.10.0 --recursive https://github.com/rustls/rustls-ffi.git
         cd rustls-ffi
         make DESTDIR=$HOME/rustls install
       name: 'install rustls'

docs/RUSTLS.md

@@ -3,7 +3,7 @@
 [Rustls is a TLS backend written in Rust](https://docs.rs/rustls/). Curl can
 be built to use it as an alternative to OpenSSL or other TLS backends. We use
 the [rustls-ffi C bindings](https://github.com/rustls/rustls-ffi/). This
-version of curl depends on version v0.9.2 of rustls-ffi.
+version of curl depends on version v0.10.0 of rustls-ffi.
 
 # Building with rustls
 
@@ -12,7 +12,7 @@ First, [install Rust](https://rustup.rs/).
 Next, check out, build, and install the appropriate version of rustls-ffi:
 
     % cargo install cbindgen
-    % git clone https://github.com/rustls/rustls-ffi -b v0.9.2
+    % git clone https://github.com/rustls/rustls-ffi -b v0.10.0
     % cd rustls-ffi
     % make
     % make DESTDIR=${HOME}/rustls-ffi-built/ install