Set naclsdk_mode=manual and source tools/llvm/setup_arm_untrusted_toolchain.sh if mode is misc-tools.
Set naclsdk_mode=manual and source tools/llvm/setup_arm_untrusted_toolchain.sh
if mode is misc-tools.

Without this change a build of the trusted toolchain was failing because
it was trying to use the x86 setup in _SetEnvForX86Sdk.

I wonder if the else in  generate in naclsdk.py should be an assert and
not a call to _SetEnvForX86Sdk.

Review URL: http://codereview.chromium.org/567032

git-svn-id: 721b910a23eff8a86f00c8fd261a7587cddf18f8@1458 fcba33aa-ac0c-11dd-b9e7-8d5594d729c2

nacl-webkit/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client,nacl-webkit/native_client,sbc100/native_client,nacl-webkit/native_client,nacl-webkit/native_client,sbc100/native_client,nacl-webkit/native_client,sbc100/native_client