runtime: drop redundant argument to getArgInfo

The f funcInfo argument is always the same as frame.fn, so we don't
need to pass it. I suspect that was there to make the signatures of
getArgInfoFast and getArgInfo more similar, but it's not necessary.

For #54466.

Change-Id: Idc717f4df09e97cad49d52c5b7edf28090908cba
Reviewed-on: https://go-review.googlesource.com/c/go/+/424255
Run-TryBot: Austin Clements <[email protected]>
Auto-Submit: Austin Clements <[email protected]>
Reviewed-by: Michael Pratt <[email protected]>
Reviewed-by: Cherry Mui <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>

Author: aclements

src/runtime/traceback.go

@@ -294,7 +294,7 @@ func gentraceback(pc0, sp0, lr0 uintptr, gp *g, skip int, pcbuf *uintptr, max in
 			var ok bool
 			frame.arglen, frame.argmap, ok = getArgInfoFast(f, callback != nil)
 			if !ok {
-				frame.arglen, frame.argmap = getArgInfo(&frame, f, callback != nil)
+				frame.arglen, frame.argmap = getArgInfo(&frame, callback != nil)
 			}
 		}
 
@@ -679,7 +679,8 @@ func getArgInfoFast(f funcInfo, needArgMap bool) (arglen uintptr, argmap *bitvec
 
 // getArgInfo returns the argument frame information for a call to f
 // with call frame frame.
-func getArgInfo(frame *stkframe, f funcInfo, needArgMap bool) (arglen uintptr, argmap *bitvector) {
+func getArgInfo(frame *stkframe, needArgMap bool) (arglen uintptr, argmap *bitvector) {
+	f := frame.fn
 	arglen = uintptr(f.args)
 	if needArgMap && f.args == _ArgsSizeUnknown {
 		// Extract argument bitmaps for reflect stubs from the calls they made to reflect.