small cleanup in src/compat .h and .cpp

- add license header
- fix include guards
- fix indentation

src/compat/glibc_compat.cpp

@@ -1,19 +1,28 @@
+// Copyright (c) 2009-2014 The Bitcoin developers
+// Distributed under the MIT/X11 software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#if defined(HAVE_CONFIG_H)
 #include "bitcoin-config.h"
+#endif
+
 #include <cstddef>
+#if defined(HAVE_SYS_SELECT_H)
 #include <sys/select.h>
+#endif
 
 // Prior to GLIBC_2.14, memcpy was aliased to memmove.
 extern "C" void* memmove(void* a, const void* b, size_t c);
 extern "C" void* memcpy(void* a, const void* b, size_t c)
 {
-  return memmove(a, b, c);
+    return memmove(a, b, c);
 }
 
 extern "C" void __chk_fail (void) __attribute__((__noreturn__));
 extern "C" FDELT_TYPE __fdelt_warn(FDELT_TYPE a)
 {
-  if (a >= FD_SETSIZE)
-    __chk_fail ();
-  return a / __NFDBITS;
+    if (a >= FD_SETSIZE)
+        __chk_fail ();
+    return a / __NFDBITS;
 }
 extern "C" FDELT_TYPE __fdelt_chk(FDELT_TYPE) __attribute__((weak, alias("__fdelt_warn")));