Disable running of sel_ldr arm tests on mac

ports/zlib/build.sh

 # Copyright (c) 2011 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # zlib doesn't support custom build directories so we have
 # to build directly in the source dir.
 BUILD_DIR=${SRC_DIR}
 EXECUTABLES="minigzip${NACL_EXEEXT} example${NACL_EXEEXT}"
 if [ "${NACL_SHARED}" = "1" ]; then
   EXECUTABLES+=" libz.so.1"
@@ skipping 36 matching lines @@
   else \
     echo '  *** zlib test FAILED ***'; \
     exit 1
   fi
   unset SEL_LDR_LIB_PATH
 }
 
 TestStep() {
   RunExample
   RunMinigzip
-  if [ "${NACL_ARCH}" = "pnacl" ]; then
+  if [[ ${NACL_ARCH} == pnacl ]]; then
     # Run the minigzip tests again but with x86-32 and arm translations
     WriteLauncherScript minigzip minigzip.x86-32.nexe
     RunMinigzip
-    WriteLauncherScript minigzip minigzip.arm.nexe
-    RunMinigzip
+    if [[ ${SEL_LDR_SUPPORTS_ARM} == 1 ]]; then
+      WriteLauncherScript minigzip minigzip.arm.nexe
+      RunMinigzip
+    fi
   fi
 }