staging: rtl8723au: collect_bss_info23a(): Eliminate smatch warning
staging: rtl8723au: collect_bss_info23a(): Eliminate smatch warning

Make length an unsigned int. This should avoid Smatch warning that
'length' can go negative.

Reported-by: Dan Carpenter <ff341aa343d564f9e53e9dcb6996be8c04859a66@oracle.com>
Signed-off-by: Jes Sorensen <0e1e349bdba396f044a06b01fef702e072aa66d3@redhat.com>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs