expose static_libcpp feature (#464)

#463 forget to expose `static_libcpp` feature to top level Cargo.toml. Fixing it.
Signed-off-by: Yi Wu <yiwu@pingcap.com>

.travis.yml

@@ -15,9 +15,6 @@ matrix:
   - os: osx
     osx_image: xcode11.3
     rust: stable
-  - os: linux
-    arch: arm64
-    rust: stable
   - os: linux
     rust: nightly
     env: FEATURES="encryption,jemalloc,portable,sse"

Cargo.toml

@@ -20,6 +20,7 @@ encryption = ["librocksdb_sys/encryption"]
 jemalloc = ["librocksdb_sys/jemalloc"]
 portable = ["librocksdb_sys/portable"]
 sse = ["librocksdb_sys/sse"]
+static_libcpp = ["librocksdb_sys/static_libcpp"]
 valgrind = []
 
 [dependencies]

librocksdb_sys/Cargo.toml

@@ -18,13 +18,13 @@ tempfile = "3.1"
 
 [features]
 default = []
-static_libcpp = []
 encryption = ["openssl-sys"]
 jemalloc = ["jemalloc-sys"]
 # portable doesn't require static link, though it's meaningless
 # when not using with static-link right now in this crate.
 portable = ["libtitan_sys/portable"]
 sse = ["libtitan_sys/sse"]
+static_libcpp = []
 
 [build-dependencies]
 cc = "1.0.3"