Put powerpc-unknown-freebsd support to mod.rs

Author: pkubaj

src/unix/bsd/freebsdlike/freebsd/mod.rs

@@ -1698,6 +1698,9 @@ cfg_if! {
     } else if #[cfg(target_arch = "powerpc64")] {
         mod powerpc64;
         pub use self::powerpc64::*;
+    } else if #[cfg(target_arch = "powerpc")] {
+        mod powerpc;
+        pub use self::powerpc::*;
     } else {
         // Unknown target_arch
     }