Remove obsolete __BRILLO__ ifdef.

Confirmed with Brillo TL this is not needed.

Bug: 33620501
Test: Builds, boots on HiKey.
Change-Id: I8d6b7cc2a94e668d63421c456d38fe23877c3cf0

init/init.cpp

@@ -352,10 +352,6 @@ static int set_mmap_rnd_bits_action(const std::vector<std::string>& args)
     ERROR("Unknown architecture\n");
 #endif
 
-#ifdef __BRILLO__
-    // TODO: b/27794137
-    ret = 0;
-#endif
     if (ret == -1) {
         LOG(ERROR) << "Unable to set adequate mmap entropy value!";
         security_failure();