Pull in liblibc & compiler-rt changes for ARM MUSL support.

Author: timonvo

src/bootstrap/build/native.rs

@@ -124,8 +124,14 @@ pub fn compiler_rt(build: &Build, target: &str) {
                                           target.contains("freebsd") ||
                                           target.contains("netbsd") {
         let os = if target.contains("android") {"-android"} else {""};
-        let arch = if arch.starts_with("arm") && target.contains("eabihf") {
+        let arch = if arch.starts_with("armv7") {
+          "armv7"
+        } else if arch.starts_with("arm") {
+          if target.contains("eabihf") || target.contains("android") {
             "armhf"
+          } else {
+            "arm"
+          }
         } else {
             arch
         };