libstd-rs: stop using shared source

Convert libstd-rs to not use the shared source setup and instead use
its own extracted directory. Include the version info in the bitbake
file so that in the future we can support multiple versions via a
PREFERRED_VERSIONS variable.

recipes-devtools/rust/libstd-rs_1.10.0.bb

@@ -2,9 +2,15 @@ SUMMARY = "Rust standard libaries"
 HOMEPAGE = "http://www.rust-lang.org"
 SECTION = "devel"
 LICENSE = "MIT | Apache-2.0"
-
 LIC_FILES_CHKSUM ="file://COPYRIGHT;md5=43e1f1fb9c0ee3af66693d8c4fecafa8"
-require rust-shared-source.inc
+
+SRC_URI = "\
+	https://static.rust-lang.org/dist/rustc-${PV}-src.tar.gz;name=rust \
+    "
+SRC_URI[rust.md5sum] = "a48fef30353fc9daa70b484b690ce5db"
+SRC_URI[rust.sha256sum] = "a4015aacf4f6d8a8239253c4da46e7abaa8584f8214d1828d2ff0a8f56176869"
+
+S = "${WORKDIR}/rustc-${PV}"
 
 CARGO_INDEX_COMMIT = "6127fc24b0b6fe73fe4d339817fbf000b9a798a2"
 
@@ -21,7 +27,7 @@ inherit cargo
 # Needed so cargo can find libbacktrace
 RUSTFLAGS += "-L ${STAGING_LIBDIR}"
 
-B = "${WORKDIR}/build"
+S = "${WORKDIR}/rustc-${PV}"
 
 do_compile_prepend () {
     cd ${S}/src/rustc/std_shim