Do not run the altivec tests for powerpc64

The big endian variant will be supported properly later.

Author: lu-zero

.travis.yml

@@ -17,7 +17,7 @@ matrix:
     - env: TARGET=mips64-unknown-linux-gnuabi64 NORUN=1
     - env: TARGET=mips64el-unknown-linux-gnuabi64 NORUN=1
     - env: TARGET=powerpc-unknown-linux-gnu
-    - env: TARGET=powerpc64-unknown-linux-gnu
+    - env: TARGET=powerpc64-unknown-linux-gnu STDSIMD_TEST_NORUN=1
     - env: TARGET=powerpc64le-unknown-linux-gnu
     - os: osx
       env: TARGET=i686-apple-darwin