n5100: add SECONDARY_STORAGE back
n5100: add SECONDARY_STORAGE back

Change-Id: I7742bf576a4ee4e6261856e5d2a27ab4be9ba7ca

omnirom/android_device_samsung_n5100,tejkkarani/device_samsung_n5100,CyanogenMod/android_device_samsung_n5100,CyanogenMod/android_device_samsung_n5100,SlimRoms/device_samsung_n5100,DirtyUnicorns/android_device_samsung_n5100,Split-Screen/android_device_samsung_n5100,Split-Screen/android_device_samsung_n5100,SlimRoms/device_samsung_n5100,TeamWin/android_device_samsung_n5100,tejkkarani/device_samsung_n5100,CyanogenMod/android_device_samsung_n5100,cyandream-devices/android_device_samsung_n5100,cyandream-devices/android_device_samsung_n5100,TeamWin/android_device_samsung_n5100,omnirom/android_device_samsung_n5100,DirtyUnicorns/android_device_samsung_n5100,Split-Screen/android_device_samsung_n5100