Use '#ifdef' to check for CONFIG_xxx definitions

drivers/scsi/scsi.h

@@ -193,7 +193,7 @@ extern const char *const scsi_device_types[MAX_SCSI_DEVICE_CODE];
 #define SCSI_LOG_HLCOMPLETE_BITS          3
 #define SCSI_LOG_IOCTL_BITS               3
 
-#if CONFIG_SCSI_LOGGING
+#ifdef CONFIG_SCSI_LOGGING
 
 #define SCSI_CHECK_LOGGING(SHIFT, BITS, LEVEL, CMD)     \
 {                                                       \

include/asm-i386/io.h

@@ -49,7 +49,7 @@
  * Temporary debugging check to catch old code using
  * unmapped ISA addresses. Will be removed in 2.4.
  */
-#if CONFIG_DEBUG_IOVIRT
+#ifdef CONFIG_DEBUG_IOVIRT
   extern void *__io_virt_debug(unsigned long x, const char *file, int line);
   #define __io_virt(x) __io_virt_debug((unsigned long)(x), __FILE__, __LINE__)
 #else