[master] 4ef8289 remove extra [ in the usage

[Nils Goroll]

commit 4ef8289279aae89354674fc2fb1c746c4e8b4fe4
Author: Nils Goroll <nils.goroll at uplex.de>
Date:   Tue Jul 26 00:40:20 2016 +0200

    remove extra [ in the usage
    
    Thx @fgs

diff --git a/bin/varnishhist/varnishhist_options.h b/bin/varnishhist/varnishhist_options.h
index bcebdfd..682d1e1 100644
--- a/bin/varnishhist/varnishhist_options.h
+++ b/bin/varnishhist/varnishhist_options.h
@@ -46,7 +46,7 @@
 	)
 
 #define HIS_OPT_P							\
-	VOPT("P:", "[-P <[[cb:]tag:field_num:min:max>]",		\
+	VOPT("P:", "[-P <[cb:]tag:field_num:min:max>]",		\
 	    "Custom profile definition",				\
 	    " Graph the given custom definition defined as: an optional"\
 	    " (c)lient or (b)backend filter (defaults to client), the " \