bench: remove RUSTFLAGS

We no longer need to enable SIMD optimizations at compile time. They are
automatically enabled when regex is compiled with the `unstable`
feature.

bench/compile

@@ -1,8 +1,5 @@
 #!/bin/sh
 
-# Enable SIMD.
-export RUSTFLAGS="-C target-cpu=native"
-
 exec cargo build \
   --release \
   --features 're-re2 re-onig re-pcre1 re-pcre2 re-rust re-rust-bytes re-tcl re-dphobos-dmd re-dphobos-ldc' \

bench/run

@@ -9,11 +9,6 @@ if [ $# = 0 ] || [ $1 = '-h' ] || [ $1 = '--help' ]; then
   usage
 fi
 
-# Enable SIMD, unless we're in CI, then we inherit RUSTLFAGS.
-if [ -z "$TRAVIS_RUST_VERSION" ]; then
-  export RUSTFLAGS="-C target-cpu=native"
-fi
-
 which="$1"
 shift
 case $which in