Fix duplicated methods for POSIX platforms.

src/platform-freebsd.cc

Index: src/platform-freebsd.cc
diff --git a/src/platform-freebsd.cc b/src/platform-freebsd.cc
index c771cd3be029aea168a1333a57a5481690354518..a0e0dbfd054c5da9373829b566a932759f7d6c9b 100644
--- a/src/platform-freebsd.cc
+++ b/src/platform-freebsd.cc
@@ -80,11 +80,6 @@ double ceiling(double x) {
 static Mutex* limit_mutex = NULL;
 
 
-void OS::PostSetUp() {
-  POSIXPostSetUp();
-}
-
-
 uint64_t OS::CpuFeaturesImpliedByPlatform() {
   return 0;  // FreeBSD runs on anything.
 }
@@ -139,11 +134,6 @@ bool OS::IsOutsideAllocatedSpace(void* address) {
 }
 
 
-size_t OS::AllocateAlignment() {
-  return getpagesize();
-}
-
-
 void* OS::Allocate(const size_t requested,
                    size_t* allocated,
                    bool executable) {
@@ -161,40 +151,6 @@ void* OS::Allocate(const size_t requested,
 }
 
 
-void OS::Free(void* buf, const size_t length) {
-  // TODO(1240712): munmap has a return value which is ignored here.
-  int result = munmap(buf, length);
-  USE(result);
-  ASSERT(result == 0);
-}
-
-
-void OS::Sleep(int milliseconds) {
-  unsigned int ms = static_cast<unsigned int>(milliseconds);
-  usleep(1000 * ms);
-}
-
-
-int OS::NumberOfCores() {
-  return sysconf(_SC_NPROCESSORS_ONLN);
-}
-
-
-void OS::Abort() {
-  // Redirect to std abort to signal abnormal program termination.
-  abort();
-}
-
-
-void OS::DebugBreak() {
-#if (defined(__arm__) || defined(__thumb__))
-  asm("bkpt 0");
-#else
-  asm("int $3");
-#endif
-}
-
-
 void OS::DumpBacktrace() {
   POSIXBacktraceHelper<backtrace, backtrace_symbols>::DumpBacktrace();
 }