staging: android: add pmem driver

This adds the Android pmem driver to the staging tree.

[At this point in time, it is dependent on the ARM platform, due to some
build issues that require it. - gregkh]

Signed-off-by: Rebecca Schultz <rschultz@google.com>
Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
Signed-off-by: Dima Zavin <dima@android.com>
Signed-off-by: Jamie Gennis <jgennis@google.com>
Cc: Brian Swetland <swetland@google.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Colin Cross <ccross@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>