cmd/link: use __got as the .got section name

The __nl_symbol_ptr is not a common section name anymore. LLVM prefers
__got for GOT symbols in the __DATA_CONST segment.

Note that the Go linker used to place the GOT section in the __DATA
segment, but since CL 644055 we place it in the __DATA_CONST segment.

Updates #71416.

Cq-Include-Trybots: luci.golang.try:gotip-darwin-amd64-longtest
Change-Id: Icb776e19855eaabb4777a9b1eb433497842413b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/652555
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>

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

@@ -461,7 +461,7 @@ func (ctxt *Link) domacho() {
 		sb.SetType(sym.SMACHOPLT)
 		sb.SetReachable(true)
 
-		s = ctxt.loader.LookupOrCreateSym(".got", 0) // will be __nl_symbol_ptr
+		s = ctxt.loader.LookupOrCreateSym(".got", 0) // will be __got
 		sb = ctxt.loader.MakeSymbolUpdater(s)
 		if ctxt.UseRelro() {
 			sb.SetType(sym.SMACHORELROSECT)
@@ -587,7 +587,7 @@ func machoshbits(ctxt *Link, mseg *MachoSeg, sect *sym.Section, segname string)
 	}
 
 	if sect.Name == ".got" {
-		msect.name = "__nl_symbol_ptr"
+		msect.name = "__got"
 		msect.flag = S_NON_LAZY_SYMBOL_POINTERS
 		msect.res1 = uint32(ctxt.loader.SymSize(ctxt.ArchSyms.LinkEditPLT) / 4) /* offset into indirect symbol table */
 	}

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

@@ -37,7 +37,7 @@ func TestMachoSectionsReadOnly(t *testing.T) {
 			args:             []string{"-ldflags", "-linkmode=internal"},
 			prog:             prog,
 			mustInternalLink: true,
-			wantSecsRO:       []string{"__nl_symbol_ptr", "__rodata", "__itablink", "__typelink", "__gosymtab", "__gopclntab"},
+			wantSecsRO:       []string{"__got", "__rodata", "__itablink", "__typelink", "__gosymtab", "__gopclntab"},
 		},
 		{
 			name:        "linkmode-external",