serial: bfin_5xx: fix building as module when early printk is enabled

Since early printk only makes sense/works when the serial driver is built
into the kernel, disable the option for this driver when it is going to be
built as a module.  Otherwise we get build failures due to the ifdef
handling.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/serial/bfin_5xx.c

@@ -38,6 +38,10 @@
 #include <asm/cacheflush.h>
 #endif
 
+#ifdef CONFIG_SERIAL_BFIN_MODULE
+# undef CONFIG_EARLY_PRINTK
+#endif
+
 /* UART name and device definitions */
 #define BFIN_SERIAL_NAME	"ttyBF"
 #define BFIN_SERIAL_MAJOR	204