Remove unreachable and duplicated return statement

I’m confident blame will show I am at fault here, not sure how I missed it, and why `go vet` didn’t catch it either.

internal/encoding/ssh/filexfer/attrs.go

@@ -74,7 +74,6 @@ func (a *Attributes) SetPermissions(perms FileMode) {
 // GetACModTime returns the ATime and MTime fields and a bool that is true if and only if the values are valid/defined.
 func (a *Attributes) GetACModTime() (atime, mtime uint32, ok bool) {
 	return a.ATime, a.MTime, a.Flags&AttrACModTime != 0
-	return a.ATime, a.MTime, a.Flags&AttrACModTime != 0
 }
 
 // SetACModTime is a convenience function that sets the ATime and MTime fields,