git-config.1: remove value from positional args in unset usage

The synopsis for `git config unset` mentions two positional arguments:
`<name>` and `<value>`. While the first argument is correct, the second
is not. Users are expected to provide the value via `--value=<value>`.

Remove the positional argument. The `--value=<value>` option is already
documented correctly, so this is all we need to do to fix the
documentation.

Signed-off-by: Josh Heinrichs <joshiheinrichs@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-config.txt

@@ -12,7 +12,7 @@ SYNOPSIS
 'git config list' [<file-option>] [<display-option>] [--includes]
 'git config get' [<file-option>] [<display-option>] [--includes] [--all] [--regexp] [--value=<value>] [--fixed-value] [--default=<default>] <name>
 'git config set' [<file-option>] [--type=<type>] [--all] [--value=<value>] [--fixed-value] <name> <value>
-'git config unset' [<file-option>] [--all] [--value=<value>] [--fixed-value] <name> <value>
+'git config unset' [<file-option>] [--all] [--value=<value>] [--fixed-value] <name>
 'git config rename-section' [<file-option>] <old-name> <new-name>
 'git config remove-section' [<file-option>] <name>
 'git config edit' [<file-option>]

builtin/config.c

@@ -19,7 +19,7 @@ static const char *const builtin_config_usage[] = {
 	N_("git config list [<file-option>] [<display-option>] [--includes]"),
 	N_("git config get [<file-option>] [<display-option>] [--includes] [--all] [--regexp] [--value=<value>] [--fixed-value] [--default=<default>] <name>"),
 	N_("git config set [<file-option>] [--type=<type>] [--all] [--value=<value>] [--fixed-value] <name> <value>"),
-	N_("git config unset [<file-option>] [--all] [--value=<value>] [--fixed-value] <name> <value>"),
+	N_("git config unset [<file-option>] [--all] [--value=<value>] [--fixed-value] <name>"),
 	N_("git config rename-section [<file-option>] <old-name> <new-name>"),
 	N_("git config remove-section [<file-option>] <name>"),
 	N_("git config edit [<file-option>]"),
@@ -43,7 +43,7 @@ static const char *const builtin_config_set_usage[] = {
 };
 
 static const char *const builtin_config_unset_usage[] = {
-	N_("git config unset [<file-option>] [--all] [--value=<value>] [--fixed-value] <name> <value>"),
+	N_("git config unset [<file-option>] [--all] [--value=<value>] [--fixed-value] <name>"),
 	NULL
 };