Fix make check

Summary: Fix make check.  Benchmark.cpp was included twice, eventfd doesn't exist anymore.

Test Plan: autoreconf -i; ./configure; make check on ubuntu

Reviewed By: pgriess@fb.com

FB internal diff: D1259706

folly/Makefile.am

@@ -167,7 +167,6 @@ GroupVarintTables.cpp: build/generate_varint_tables.py
 CLEANFILES += GroupVarintTables.cpp
 
 libfolly_la_SOURCES = \
-	Benchmark.cpp \
 	Bits.cpp \
 	Conv.cpp \
 	Demangle.cpp \

folly/test/Makefile.am

@@ -61,12 +61,6 @@ fbstring_test_using_jemalloc_SOURCES = FBStringTest.cpp
 fbstring_test_using_jemalloc_LDADD = libgtestmain.la $(top_builddir)/libfollybenchmark.la $(top_builddir)/libfolly.la
 TESTS += fbstring_test_using_jemalloc
 
-if HAVE_LINUX
-eventfd_test_SOURCES = EventFDTest.cpp
-eventfd_test_LDADD = libgtestmain.la $(top_builddir)/libfollybenchmark.la $(top_builddir)/libfolly.la
-TESTS += eventfd_test
-endif
-
 thread_cached_int_test_SOURCES = ThreadCachedIntTest.cpp
 thread_cached_int_test_LDADD = libgtestmain.la $(top_builddir)/libfollybenchmark.la $(top_builddir)/libfolly.la