ARM: SAMSUNG: Replace inclusion of plat/regs-serial.h header file

regs-serial.h only includes linux/serial_s3c.h. Include this header
directly to remove unnecessary platform dependency.

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
[broonie@linaro.org: Acked for S3C64XX related changes]
Acked-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/mach-s3c24xx/include/mach/debug-macro.S

@@ -14,7 +14,7 @@
 
 #include <mach/map.h>
 #include <mach/regs-gpio.h>
-#include <plat/regs-serial.h>
+#include <linux/serial_s3c.h>
 
 #define S3C2410_UART1_OFF (0x4000)
 #define SHIFT_2440TXF (14-9)