Remove `if_let` feature as it has now been integrated
diff --git a/libjit-sys/Cargo.lock b/libjit-sys/Cargo.lock
index 3812c55..cb8defd 100644
--- a/libjit-sys/Cargo.lock
+++ b/libjit-sys/Cargo.lock
@@ -2,11 +2,11 @@
 name = "libjit-sys"
 version = "0.0.1"
 dependencies = [
- "pkg-config 0.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pkg-config 0.1.0 (git+https://github.com/alexcrichton/pkg-config-rs)",
 ]

 [[package]]
 name = "pkg-config"
-version = "0.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
+version = "0.1.0"
+source = "git+https://github.com/alexcrichton/pkg-config-rs#9b3b44a2e1a8ccc70c3f701aeb5154ad79e665e9"
Use `crates.io` as host for pkg-config