Add lzmadec command

I needed to be able to uncompress lzma files. I did this command
based on unzip command and propose it if it could help.

Signed-off-by: Patrice Bouchand <pbfwdlist@gmail.com>
Changed to work with sandbox
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/common/Makefile b/common/Makefile
index e2ff0cb..cecd81a 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -159,6 +159,9 @@
 obj-$(CONFIG_CMD_UBIFS) += cmd_ubifs.o
 obj-$(CONFIG_CMD_UNIVERSE) += cmd_universe.o
 obj-$(CONFIG_CMD_UNZIP) += cmd_unzip.o
+ifdef CONFIG_LZMA
+obj-$(CONFIG_CMD_LZMADEC) += cmd_lzmadec.o
+endif
 ifdef CONFIG_CMD_USB
 obj-y += cmd_usb.o
 obj-y += usb.o usb_hub.o