Fix unchecked result skin_parse_tag() exposed by r28480.

It caused the parser to not see that skin parsing failed and to enter an infinite loop.
And as a result it continued to endlessly malloc(). In normal build the skin buffer size limit made it end.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@28497 a1c6a512-1295-4272-9138-f99709370657
1 file changed