SnapdragonGallery:Fix gallery crash while loading content

Application is loading a texture of type RGB565
of size 483x483 without setting pixel alignment
value (by glPixelStorei), so driver picks the
default alignment value of 4, due to which while
copying the data from client memory, sigsev is
triggered because of wrong alignment, hence the crash.

Change-Id: Ie133105fb3c24538288d8cc787e4945f755bb408
CRs-Fixed:1056207