addpatch: deltachat-rpc-server

- Add fix for time-rs/time#696
- Patch ring 0.16.20

deltachat-rpc-server/riscv64.patch

@@ -0,0 +1,12 @@
+--- PKGBUILD
++++ PKGBUILD
+@@ -26,6 +26,9 @@ b2sums=('10dcae7ef8aab28b26bebc39cecd4e1b3ed38195c51e9b50637451f778392d9fd15efb4
+ prepare() {
+   export RUSTUP_TOOLCHAIN=stable
+   cd $_upstream-$pkgver
++  cargo update -p [email protected]
++  echo -e "\n[patch.crates-io]\nring = { git = 'https://github.com/felixonmars/ring', branch = '0.16.20' }" >> Cargo.toml
++  cargo update -p [email protected]
+   cargo fetch --locked --target "$(rustc -vV | sed -n 's/host: //p')"
+
+ }