Added thumbv6 target

Author: farcaller

Cargo.toml

@@ -14,6 +14,9 @@ environments where another libc does not exist, since rustc may
 implicitly insert calls to such functions.
 """
 
+[target.thumbv6-none-eabi.dependencies.core]
+git = "https://github.com/hackndev/rust-libcore"
+
 [target.thumbv7m-none-eabi.dependencies.core]
 git = "https://github.com/hackndev/rust-libcore"