Convert CONFIG_LZMA to Kconfig

This converts the following to Kconfig:
   CONFIG_LZMA

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/iconnect_defconfig b/configs/iconnect_defconfig
index 32994ec..3e48380 100644
--- a/configs/iconnect_defconfig
+++ b/configs/iconnect_defconfig
@@ -21,4 +21,5 @@
 CONFIG_USB=y
 CONFIG_USB_EHCI_HCD=y
 CONFIG_USB_STORAGE=y
+CONFIG_LZMA=y
 CONFIG_OF_LIBFDT=y