USB:gadget:designware Fix memory nonalignment issue

While receiving packets from FIFO sometimes the buffer provided was
nonaligned. Fix this by taking a temporary aligned buffer and then
copying the content to nonaligned buffer.

Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: Amit Virdi <amit.virdi@st.com>