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/ap121_defconfig b/configs/ap121_defconfig
index 2550aee..40055f0 100644
--- a/configs/ap121_defconfig
+++ b/configs/ap121_defconfig
@@ -50,3 +50,4 @@
 CONFIG_AR933X_UART=y
 CONFIG_DM_SPI=y
 CONFIG_ATH79_SPI=y
+CONFIG_LZMA=y