[PATCH] Constness fix for pickaxe option.

Constness fix for pickaxe option.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

diff-cache.c

@@ -8,7 +8,7 @@ static int line_termination = '\n';
 static int detect_rename = 0;
 static int reverse_diff = 0;
 static int diff_score_opt = 0;
-static char *pickaxe = 0;
+static const char *pickaxe = NULL;
 
 /* A file entry went away or appeared */
 static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)

diff-files.c

@@ -14,7 +14,7 @@ static int line_termination = '\n';
 static int detect_rename = 0;
 static int reverse_diff = 0;
 static int diff_score_opt = 0;
-static char *pickaxe = 0;
+static const char *pickaxe = NULL;
 static int silent = 0;
 
 static int matches_pathspec(struct cache_entry *ce, char **spec, int cnt)

diff-helper.c

@@ -9,7 +9,7 @@
 static int detect_rename = 0;
 static int diff_score_opt = 0;
 static int generate_patch = 1;
-static char *pickaxe = 0;
+static const char *pickaxe = NULL;
 
 static int parse_oneside_change(const char *cp, int *mode,
 				unsigned char *sha1, char *path)

diff-tree.c

@@ -13,7 +13,7 @@ static int generate_patch = 0;
 static int detect_rename = 0;
 static int reverse_diff = 0;
 static int diff_score_opt = 0;
-static char *pickaxe = 0;
+static const char *pickaxe = NULL;
 static const char *header = NULL;
 static const char *header_prefix = "";
 

diff.c

@@ -513,7 +513,7 @@ int diff_scoreopt_parse(const char *opt)
 }
 
 void diff_setup(int detect_rename_, int minimum_score_,
-		char *pickaxe_,
+		const char *pickaxe_,
 		int reverse_diff_, int diff_raw_output_,
 		const char **pathspec_, int speccnt_)
 {

diff.h

@@ -20,7 +20,7 @@ extern void diff_unmerge(const char *path);
 extern int diff_scoreopt_parse(const char *opt);
 
 extern void diff_setup(int detect_rename, int minimum_score,
-		       char *pickaxe,
+		       const char *pickaxe,
 		       int reverse, int raw_output,
 		       const char **spec, int cnt);