net: usb: aqc111: Fix out-of-bounds accesses in RX fixup

In the Linux kernel, the following vulnerability has been resolved:

net: usb: aqc111: Fix out-of-bounds accesses in RX fixup

aqc111_rx_fixup() contains several out-of-bounds accesses that can be
triggered by a malicious (or defective) USB device, in particular:

- The metadata array (desc_offset..desc_offset+2*pkt_count) can be out of bounds,
causing OOB reads and (on big-endian systems) OOB endianness flips.
- A packet can overlap the metadata array, causing a later OOB
endianness flip to corrupt data used by a cloned SKB that has already
been handed off into the network stack.
- A packet SKB can be constructed whose tail is far beyond its end,
causing out-of-bounds heap data to be considered part of the SKB's
data.

Found doing variant analysis. Tested it with another driver (ax88179_178a), since
I don't have a aqc111 device to test it, but the code looks very similar.