strvec: use correct member name in comments

In d70a9eb (strvec: rename struct fields, 2020-07-28), we renamed the
"argv" member to "v". In the same patch we also did the following rename
in strvec.c:

    -void strvec_pushv(struct strvec *array, const char **argv)
    +void strvec_pushv(struct strvec *array, const char **items)

and it appears that this s/argv/items operation was erroneously applied
to strvec.h.

Rename "items" to "v".

Signed-off-by: Linus Arver <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: Linus Arver

strvec.h

@@ -4,8 +4,8 @@
 /**
  * The strvec API allows one to dynamically build and store
  * NULL-terminated arrays of strings. A strvec maintains the invariant that the
- * `items` member always points to a non-NULL array, and that the array is
- * always NULL-terminated at the element pointed to by `items[nr]`. This
+ * `v` member always points to a non-NULL array, and that the array is
+ * always NULL-terminated at the element pointed to by `v[nr]`. This
  * makes the result suitable for passing to functions expecting to receive
  * argv from main().
  *
@@ -22,7 +22,7 @@ extern const char *empty_strvec[];
 
 /**
  * A single array. This should be initialized by assignment from
- * `STRVEC_INIT`, or by calling `strvec_init`. The `items`
+ * `STRVEC_INIT`, or by calling `strvec_init`. The `v`
  * member contains the actual array; the `nr` member contains the
  * number of elements in the array, not including the terminating
  * NULL.
@@ -80,7 +80,7 @@ void strvec_split(struct strvec *, const char *);
 void strvec_clear(struct strvec *);
 
 /**
- * Disconnect the `items` member from the `strvec` struct and
+ * Disconnect the `v` member from the `strvec` struct and
  * return it. The caller is responsible for freeing the memory used
  * by the array, and by the strings it references. After detaching,
  * the `strvec` is in a reinitialized state and can be pushed