[CIFS] clean up some hard to read ifdefs

Christoph had noticed too many ifdefs in the CIFS code making it
hard to read.  This patch removes about a quarter of them from
the C files in cifs by improving a few key ifdefs in the .h files.

Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/cifs_debug.h b/fs/cifs/cifs_debug.h
index 90e7624..5eb3b83 100644
--- a/fs/cifs/cifs_debug.h
+++ b/fs/cifs/cifs_debug.h
@@ -25,8 +25,11 @@
 
 void cifs_dump_mem(char *label, void *data, int length);
 #ifdef CONFIG_CIFS_DEBUG2
+#define DBG2 2
 void cifs_dump_detail(struct smb_hdr *);
 void cifs_dump_mids(struct TCP_Server_Info *);
+#else
+#define DBG2 0
 #endif
 extern int traceSMB;		/* flag which enables the function below */
 void dump_smb(struct smb_hdr *, int);