debug/gdb: disable nls when CT_TOOLCHAIN_ENABLE_NLS is not selected

Signed-off-by: Zhenqiang Chen <zhenqiang.chen@linaro.org>
Message-Id: <CACgzC7Bn+WpbgDruNeZ4s1z0x1deF6n4YyS22Dy7p_d1fFDVCA@mail.gmail.com>
PatchWork-Id: 191042

 # Alpha specific configuration file

 ## select ARCH_SUPPORTS_32

 ## select ARCH_DEFAULT_32

 ## select ARCH_USE_MMU

 ## select ARCH_SUPPORTS_WITH_CPU

 ## select ARCH_SUPPORTS_WITH_TUNE

 ##

 ## help The Alpha architecture.