Disable running of sel_ldr arm tests on mac

ports/jpeg8d/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.
 
 EXECUTABLES="rdjpgcom${NACL_EXEEXT} wrjpgcom${NACL_EXEEXT} \
       cjpeg${NACL_EXEEXT} djpeg${NACL_EXEEXT} jpegtran${NACL_EXEEXT}"
 
+RunTestsPnacl() {
+  local arch=$1
+  for exe in ${EXECUTABLES}; do
+    local exe_noext=${exe%.*}
+    WriteLauncherScript ${exe_noext} ${exe_noext}.${arch}.nexe
+  done
+  LogExecute make test
+}
+
 TestStep() {
   export SEL_LDR_LIB_PATH=$PWD/.libs
 
   if [[ ${NACL_SHARED} == 1 ]]; then
     for exe in ${EXECUTABLES}; do
      local script=$(basename ${exe%.*})
       WriteLauncherScript ${script} ${exe}
     done
   fi
   LogExecute make test
 
   if [[ ${NACL_ARCH} == pnacl ]]; then
-    for arch in x86-32 arm; do
-      for exe in ${EXECUTABLES}; do
-        local exe_noext=${exe%.*}
-        WriteLauncherScript ${exe_noext} ${exe_noext}.${arch}.nexe
-      done
-      LogExecute make test
-    done
+    RunTestsPnacl x86-32
+    if [[ ${SEL_LDR_SUPPORTS_ARM} == 1 ]]; then
+      RunTestsPnacl arm
+    fi
   fi
 }