cmd: fuse: Add fuse writebuff sub-system command

Add CMD_FUSE_WRITEBUFF config option to add and enable fuse writebuff
sub-system command. Add fuse_writebuff function to be invoked on
writebuff command.

Signed-off-by: Harsha Vardhan V M <h-vm@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/cmd/Kconfig b/cmd/Kconfig
index cd391d4..81c59be 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -1236,6 +1236,14 @@
 	  which control the behaviour of the device. The command uses the
 	  fuse_...() API.
 
+config CMD_FUSE_WRITEBUFF
+	bool "Support for the fuse writebuff"
+	depends on CMD_FUSE
+	help
+	  This allows programming fuses, which control the behaviour of
+	  the device, using a structured buffer in memory. The command
+	  uses the fuse_writebuff() API.
+
 config CMD_GPIO
 	bool "gpio"
 	help