build: remove unneeded getentropy detection (HAVE_GETENTROPY)

configure.ac

@@ -1109,13 +1109,6 @@ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <unistd.h>
  [ AC_MSG_RESULT([no])]
 )
 
-AC_MSG_CHECKING([for getentropy])
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <unistd.h>]],
- [[ getentropy(nullptr, 32) ]])],
- [ AC_MSG_RESULT([yes]); AC_DEFINE([HAVE_GETENTROPY], [1], [Define this symbol if the BSD getentropy system call is available]) ],
- [ AC_MSG_RESULT([no])]
-)
-
 AC_MSG_CHECKING([for getentropy via random.h])
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <unistd.h>
  #include <sys/random.h>]],

src/random.cpp

@@ -32,10 +32,8 @@
 #include <sys/syscall.h>
 #include <linux/random.h>
 #endif
-#if defined(HAVE_GETENTROPY) || (defined(HAVE_GETENTROPY_RAND) && defined(MAC_OSX))
-#include <unistd.h>
-#endif
 #if defined(HAVE_GETENTROPY_RAND) && defined(MAC_OSX)
+#include <unistd.h>
 #include <sys/random.h>
 #endif
 #ifdef HAVE_SYSCTL_ARND