io-util: introduce iovec_array_free()

It will be used in later commits.

src/basic/io-util.c

@@ -362,3 +362,13 @@ size_t iovw_size(struct iovec_wrapper *iovw) {
 
         return n;
 }
+
+void iovec_array_free(struct iovec *iov, size_t n) {
+        if (!iov)
+                return;
+
+        for (size_t i = 0; i < n; i++)
+                free(iov[i].iov_base);
+
+        free(iov);
+}

src/basic/io-util.h

@@ -105,3 +105,5 @@ int iovw_put_string_field(struct iovec_wrapper *iovw, const char *field, const c
 int iovw_put_string_field_free(struct iovec_wrapper *iovw, const char *field, char *value);
 void iovw_rebase(struct iovec_wrapper *iovw, char *old, char *new);
 size_t iovw_size(struct iovec_wrapper *iovw);
+
+void iovec_array_free(struct iovec *iov, size_t n);