Convert CONFIG_LPUART et al to Kconfig

This converts the following to Kconfig:
   CONFIG_LPUART
   CONFIG_LPUART_32B_REG

And note that CONFIG_LPUART_32B_REG is unused in code.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/include/configs/ls1021atwr.h b/include/configs/ls1021atwr.h
index 03a4ce5..b607dd3 100644
--- a/include/configs/ls1021atwr.h
+++ b/include/configs/ls1021atwr.h
@@ -165,9 +165,7 @@
 /*
  * Serial Port
  */
-#ifdef CONFIG_LPUART
-#define CONFIG_LPUART_32B_REG
-#else
+#ifndef CONFIG_LPUART
 #define CONFIG_SYS_NS16550_SERIAL
 #ifndef CONFIG_DM_SERIAL
 #define CONFIG_SYS_NS16550_REG_SIZE	1