Defines starting with `s' in bsd/ppc

• SEGOFSET bsd/ppc/param.h:48
• SEGSHIFT bsd/ppc/param.h:49
• SP bsd/ppc/reg.h:37
• STACK_GROWTH_UP bsd/ppc/param.h:56
• STACKSIZE bsd/ppc/param.h:61
• SV_SAVE_REGS bsd/ppc/signal.h:56