advapi32: Fix ComputeStringSidSize to work with SIDs with one sub authority.

[Robert Shearman]

Use GetSidLengthRequired instead of computing the length in a way that 
won't always be correct.
---
  dlls/advapi32/security.c |   14 ++++++--------
  1 files changed, 6 insertions(+), 8 deletions(-)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 5d03bffe5b315e6ec3ad27c0caeb6ccc37f0ee92.diff
Type: text/x-patch
Size: 1866 bytes
Desc: not available
Url : http://www.winehq.org/pipermail/wine-patches/attachments/20070718/d2a7dcf8/5d03bffe5b315e6ec3ad27c0caeb6ccc37f0ee92.bin