[NEON] Remove empty test file from r335734

Fails on Green Dragon:
http://green.lab.llvm.org/green/job/clang-stage1-cmake-RA-incremental/50174/consoleFull

UNRESOLVED: Clang :: CodeGen/vld_dup.c (5546 of 38947)
******************** TEST 'Clang :: CodeGen/vld_dup.c' FAILED ********************
Test has no run line!

llvm-svn: 335750