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

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>