qcacld-3.0: check the data length when downloading firmware

When downloading a corrupted firmware file that has chunk length in
header which doesn't match the contents, buffer over-read may occur.

To fix it, before downloading the data, ensure the length is equal or
smaller than the left size of the firmware file.

Change-Id: I4e0c6c4423f94f26a8c4573b5d234296890f4ecf
CRs-Fixed: 2314182
1 file changed