knc: fix a couple of memory leaks.

One of these can be remotely triggered during the authentication
phase which leads to a remote DoS possibility.

Pointed out by: Imre Rad <radimre83@gmail.com>
gstd_release_context(void *ctx) {
	OM_uint32	min;

	gss_delete_sec_context(&min, (gss_ctx_id_t *)ctx, GSS_C_NO_BUFFER);
}

gstd_release_context(void *ctx) {
	OM_uint32	min;

	gss_delete_sec_context(&min, (gss_ctx_id_t *)ctx, GSS_C_NO_BUFFER);
}
