fs/file: unify prefix about file_xxx api, like file_open, file_ioctl

old:
fs_getfilep, fs_putfilep, fs_reffilep
new:
file_get, file_put, file_ref

Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>

fs/procfs/fs_procfsproc.c

@@ -1333,7 +1333,7 @@ static ssize_t proc_groupfd(FAR struct proc_file_s *procfile,
           procfile->line[linesize - 2] = '\n';
         }
 
-      fs_putfilep(filep);
+      file_put(filep);
       copysize   = procfs_memcpy(procfile->line, linesize,
                                  buffer, remaining, &offset);