tcp: fix a size_t < 0 comparison in tcp_read_sock
tcp: fix a size_t < 0 comparison in tcp_read_sock

<used> should be of type int (not size_t) since recv_actor can return
negative values and it is also used in a < 0 comparison.

Signed-off-by: Octavian Purdila <91308da0bf7e40e0a8ed5b7ced492510cbb48f46@ixiacom.com>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas