runtime: remove unused export_test declarations

Change-Id: Iac28c4bbe949af5628cef8ecafdd59ab5d71e6cc
Reviewed-on: https://go-review.googlesource.com/2240Reviewed-by: Keith Randall <khr@golang.org>

src/runtime/export_test.go

@@ -18,9 +18,6 @@ var Fcmp64 = fcmp64
 var Fintto64 = fintto64
 var F64toint = f64toint
 
-// in asm_*.s
-func stackguard() (sp, limit uintptr)
-
 var Entersyscall = entersyscall
 var Exitsyscall = exitsyscall
 var LockedOSThread = lockedOSThread
@@ -30,9 +27,6 @@ type LFNode struct {
 	Pushcnt uintptr
 }
 
-func lfstackpush_m()
-func lfstackpop_m()
-
 func LFStackPush(head *uint64, node *LFNode) {
 	lfstackpush(head, (*lfnode)(unsafe.Pointer(node)))
 }
@@ -52,11 +46,6 @@ type ParFor struct {
 	wait    bool
 }
 
-func newparfor_m()
-func parforsetup_m()
-func parfordo_m()
-func parforiters_m()
-
 func NewParFor(nthrmax uint32) *ParFor {
 	var desc *ParFor
 	systemstack(func() {