runtime: fix newosproc darwin+arm/arm64

Missed conversion of newosproc for the parts of darwin that
weren't affected by my previous change.

Update #25181

Change-Id: I81a2935e192b6d0df358c59b7e785eb03c504c23
Reviewed-on: https://go-review.googlesource.com/110123Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

src/runtime/os_darwin_raw.go

@@ -137,7 +137,8 @@ func goenvs() {
 
 // May run with m.p==nil, so write barriers are not allowed.
 //go:nowritebarrier
-func newosproc(mp *m, stk unsafe.Pointer) {
+func newosproc(mp *m) {
+	stk := unsafe.Pointer(mp.g0.stack.hi)
 	if false {
 		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " id=", mp.id, " ostk=", &mp, "\n")
 	}