Remove GTEST_SKIP()s for memfd_create().

We have other tests that require this syscall, which arrived in Linux 3.17.

Change-Id: Ie5cf327b3f3f4b0e1aa37fb2b09cde2fecbc154a
diff --git a/tests/dlext_test.cpp b/tests/dlext_test.cpp
index b8826c1..b5bf753 100644
--- a/tests/dlext_test.cpp
+++ b/tests/dlext_test.cpp
@@ -968,7 +968,6 @@
 
   // create memfd
   int memfd = memfd_create("foobar", MFD_CLOEXEC);
-  if (memfd == -1 && errno == ENOSYS) GTEST_SKIP() << "no memfd_create() in this kernel";
   ASSERT_TRUE(memfd != -1) << strerror(errno);
 
   // Check st.f_type is TMPFS_MAGIC for memfd
diff --git a/tests/sys_mman_test.cpp b/tests/sys_mman_test.cpp
index 54a0b64..85096bb 100644
--- a/tests/sys_mman_test.cpp
+++ b/tests/sys_mman_test.cpp
@@ -295,7 +295,6 @@
   // Is the MFD_CLOEXEC flag obeyed?
   errno = 0;
   int fd = memfd_create("doesn't matter", 0);
-  if (fd == -1 && errno == ENOSYS) GTEST_SKIP() << "no memfd_create() in this kernel";
   ASSERT_NE(-1, fd) << strerror(errno);
 
   int f = fcntl(fd, F_GETFD);