[SYCL] Remove object format devicelib files (#21711)
In https://github.com/intel/llvm/pull/21672, we removed .new.o format
devicelib file and use .bc format devicelib files for both new and old
offloading model driver. This PR removes .o format devicelib files since
they are not used in current pipeline either.
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Signed-off-by: jinge90 <ge.jin@intel.com>
