ARM_NEON Inline Assembly for copyLCharsFromUCharSource() inefficient for aligned destinations
https://bugs.webkit.org/show_bug.cgi?id=109335

Reviewed by Filip Pizlo.

Change a "do while" to a "while" so that we don't copy single characters to align the 
destination when it is already aligned.

* wtf/text/ASCIIFastPath.h:
(WTF::copyLCharsFromUCharSource):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@142336 268f45cc-cd09-0410-ab3c-d52691b4dbfc