Remove second FIND_PACKAGE(Torch REQUIRED)
Remove second FIND_PACKAGE(Torch REQUIRED)

On Ubuntu 12.04, the FIND_PACKAGE(Torch REQUIRED) causes a CMake error
"add_library cannot create imported target "TH" because another target
with the same name already exists". The first FIND_PACKAGE call is in
the top-level CMakeLists.txt.

Fixes #1

facebook/ztorch,facebook/ztorch