Macros starting with `s' in src/slirp

• sbflush src/slirp/sbuf.h:13
• sbspace src/slirp/sbuf.h:14
• SEQ_GEQ src/slirp/tcp.h:162
• SEQ_GT src/slirp/tcp.h:161
• SEQ_LEQ src/slirp/tcp.h:160
• SEQ_LT src/slirp/tcp.h:159
• sototcpcb src/slirp/tcp_var.h:131