fuser: bugfixes and shrink. It was assuming that xmalloc zeroes returned area!

fuser: bugfixes and shrink. It was assuming that xmalloc zeroes returned area!

function                                             old     new   delta
scan_dir_links                                         -     106    +106
add_inode                                              -      89     +89
scan_link                                              -      78     +78
file_to_dev_inode                                      -      64     +64
search_dev_inode                                       -      63     +63
add_pid                                                -      39     +39
packed_usage                                       23948   23928     -20
fuser_add_pid                                         49       -     -49
fuser_file_to_dev_inode                               64       -     -64
fuser_search_dev_inode                                77       -     -77
fuser_scan_link                                       91       -     -91
fuser_scan_dir_links                                 108       -    -108
fuser_add_inode                                      124       -    -124
fuser_main                                          1450    1243    -207
------------------------------------------------------------------------------
(add/remove: 6/6 grow/shrink: 0/2 up/down: 439/-740)         Total: -301 bytes
   text    data     bss     dec     hex filename
 798327     658    7428  806413   c4e0d busybox_old
 797988     658    7428  806074   c4cba busybox_unstripped