drivers: hwspinlock: add framework

Add a platform-independent hwspinlock framework.

Hardware spinlock devices are needed, e.g., in order to access data
that is shared between remote processors, that otherwise have no
alternative mechanism to accomplish synchronization and mutual exclusion
operations.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Hari Kanigeri <h-kanigeri2@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>

drivers/hwspinlock/Kconfig

@@ -0,0 +1,13 @@
+#
+# Generic HWSPINLOCK framework
+#
+
+config HWSPINLOCK
+	tristate "Generic Hardware Spinlock framework"
+	help
+	  Say y here to support the generic hardware spinlock framework.
+	  You only need to enable this if you have hardware spinlock module
+	  on your system (usually only relevant if your system has remote slave
+	  coprocessors).
+
+	  If unsure, say N.