added setjmp()/longjmp() (used by NetBSD x86 emulator)

modified x86pcibios.c to work with NetBSD x86 emulator

util/setjmp.S

@@ -0,0 +1,16 @@
+		.globl		_setjmp
+		.globl		_longjmp
+
+_setjmp:	move.l		4(sp),a0		// address of jmp_buf[]
+		move.l		(sp),(a0)		// save return address
+		movem.l		d2-d7/a2-a7,4(a0)	// save registers to jmp_buf
+		clr.l		d0
+		rts
+
+_longjmp:	move.l		4(sp),a0		// address of jmp_buf[]
+		move.l		8(sp),d0		// value to return
+		jne		not_0			// value may not be 0
+		moveq.l		#1,d0
+not_0:		movem.l		4(a0),d2-d7/a2-a7	// restore registers
+		move.l		(a0),(sp)		// restore saved return address
+		rts