add support for explicit_bzero in _hacl/Lib_Memzero0

(need to verify whether OpenSolaris does support explicit_bzero and then prepare a PR)

Author: kulikjak

Modules/_hacl/Lib_Memzero0.c

@@ -57,7 +57,7 @@ void Lib_Memzero0_memzero0(void *dst, uint64_t len) {
     SecureZeroMemory(dst, len_);
   #elif defined(__APPLE__) && defined(__MACH__) && defined(APPLE_HAS_MEMSET_S)
     memset_s(dst, len_, 0, len_);
-  #elif (defined(__linux__) && !defined(LINUX_NO_EXPLICIT_BZERO)) || defined(__FreeBSD__) || defined(__OpenBSD__)
+  #elif (defined(__linux__) && !defined(LINUX_NO_EXPLICIT_BZERO)) || defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__sun)
     explicit_bzero(dst, len_);
   #elif defined(__NetBSD__)
     explicit_memset(dst, 0, len_);