Enable setting security contexts on rootfs inodes.

rootfs (ramfs) can support setting of security contexts
by userspace due to the vfs fallback behavior of calling
the security module to set the in-core inode state
for security.* attributes when the filesystem does not
provide an xattr handler.  No xattr handler required
as the inodes are pinned in memory and have no backing
store.

This is useful in allowing early userspace to label individual
files within a rootfs while still providing a policy-defined
default via genfs.

Change-Id: I63abac29b265f245c47e10ba736dcf0b234edda3
writeback: Fix occasional slow sync(1)

In case when system contains no dirty pages, wakeup_flusher_threads()
will submit WB_SYNC_NONE writeback for 0 pages so wb_writeback() exits
immediately without doing anything. Thus sync(1) will write all the
dirty inodes from a WB_SYNC_ALL writeback pass which is slow.

Fix the problem by using get_nr_dirty_pages() in
wakeup_flusher_threads() instead of calculating number of dirty pages
manually. That function also takes number of dirty inodes into account.

Change-Id: If963abd73daf6a2389f97e51f1ff287f5b67871d
USB: gadget: Cleanup boot-up message with default usb composition

The print message with rmnet bind and adb_bind is enabled by default.
It appears for each default composition switch. Watchdog timeout is
seen if there is stability issue on device bootup with serial console
enable. Hence move message loglevel from pr_info to pr_debug to
resolve this issue.

Change-Id: Ieb374d75f17a0b59d05f3533e0323e0fefe0a126
Add VDD Interface preparation

Change-Id: Iec1ad4c846d7ad254b819c1bd82741d2a67464dc