watchdog: Add a simple mmap() stub for shwdt.

In some applications people have expressed a need for an mmap() method,
so we implement a simple stub for this that maps back a page with the
counter in it.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/drivers/char/watchdog/Kconfig b/drivers/char/watchdog/Kconfig
index fff89c2..f114d7b 100644
--- a/drivers/char/watchdog/Kconfig
+++ b/drivers/char/watchdog/Kconfig
@@ -510,6 +510,14 @@
 	  To compile this driver as a module, choose M here: the
 	  module will be called shwdt.
 
+config SH_WDT_MMAP
+	bool "Allow mmap of SH WDT"
+	default n
+	depends on SH_WDT
+	help
+	  If you say Y here, user applications will be able to mmap the
+	  WDT/CPG registers.
+#
 # SPARC64 Architecture
 
 config WATCHDOG_CP1XXX