ueventd: do not reference init's sehandle

Init exposes a global 'sehandle' that ueventd references as part of
devices.cpp and util.cpp.  This is particularly dangerous in
device_init() in which both uevent and init write to this global.

This change creates a separate local copy for devices.cpp and puts
restrictions on where init.h can be included to make sure the global
used by init is not reference by non-init code.  Future changes to
init should remove this global.

Test: Boot bullhead

Change-Id: Ifefa9e1932e9d647d06cca2618f5c8e5a7a85460
diff --git a/init/builtins.cpp b/init/builtins.cpp
index 1d98ef1..559fb84 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -205,7 +205,7 @@
         mode = std::strtoul(args[2].c_str(), 0, 8);
     }
 
-    ret = make_dir(args[1].c_str(), mode);
+    ret = make_dir(args[1].c_str(), mode, sehandle);
     /* chmod in case the directory already exists */
     if (ret == -1 && errno == EEXIST) {
         ret = fchmodat(AT_FDCWD, args[1].c_str(), mode, AT_SYMLINK_NOFOLLOW);
@@ -809,7 +809,7 @@
  * Callback to make a directory from the ext4 code
  */
 static int do_installkeys_ensure_dir_exists(const char* dir) {
-    if (make_dir(dir, 0700) && errno != EEXIST) {
+    if (make_dir(dir, 0700, sehandle) && errno != EEXIST) {
         return -1;
     }