[libFuzzer] fix missing close on opened file

Summary:
When running the standalone main on a large corpus, I eventually get a
EMFILE error ("Too many open files").

Patch by Paul Chaignon

Reviewers: kcc, vitalybuka

Reviewed By: vitalybuka

Subscribers: lebedev.ri, #sanitizers, llvm-commits

Tags: #llvm, #sanitizers

Differential Revision: https://reviews.llvm.org/D58622

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk/lib/fuzzer@354918 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed