diff: make it work on pipes etc (needed for kernel compile)

function                                             old     new   delta
get_recursive_dirlist                                  -     177    +177
make_temp                                              -     144    +144
diffreg                                             1818    1844     +26
files_differ                                         175     182      +7
diff_main                                            842     843      +1
get_dir                                              177       -    -177
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(add/remove: 2/1 grow/shrink: 3/0 up/down: 355/-177)          Total: 178 bytes

1 file changed