cmd/link: fix SLIBFUZZER_EXTRA_COUNTER symbol handling

Found this while deleting the old code. This should be data2.

Change-Id: I1232fac22ef63bb3a3f25a0558537cc371af3bd9
Reviewed-on: https://go-review.googlesource.com/c/go/+/234098
Run-TryBot: Cherry Zhang <[email protected]>
TryBot-Result: Gobot Gobot <[email protected]>
Reviewed-by: Than McIntosh <[email protected]>
Reviewed-by: Jeremy Faller <[email protected]>

Author: cherrymui

src/cmd/link/internal/ld/data.go

@@ -1730,7 +1730,7 @@ func (state *dodataState) allocateDataSections2(ctxt *Link) {
 	ldr.SetSymSect(ldr.LookupOrCreateSym("runtime.end", 0), sect)
 
 	// Coverage instrumentation counters for libfuzzer.
-	if len(state.data[sym.SLIBFUZZER_EXTRA_COUNTER]) > 0 {
+	if len(state.data2[sym.SLIBFUZZER_EXTRA_COUNTER]) > 0 {
 		state.allocateNamedSectionAndAssignSyms2(&Segdata, "__libfuzzer_extra_counters", sym.SLIBFUZZER_EXTRA_COUNTER, sym.Sxxx, 06)
 	}