util/os_file: fix double-close()

Fixes: 955c63d364 ("util/os_file: resize buffer to what was actually needed")
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
(cherry picked from commit 1667360f7d)

src/util/os_file.c

@@ -120,7 +120,6 @@ os_read_file(const char *filename)
    char *newbuf = realloc(buf, len);
    if (!newbuf) {
       free(buf);
-      close(fd);
       errno = -ENOMEM;
       return NULL;
    }