runtime: skip TestTimePprof if nanotime calls libc
runtime: skip TestTimePprof if nanotime calls libc

Fixes #43118

Change-Id: I499bf335904e2b72a2a8876d0368fff5e69aa7fa
Reviewed-on: https://go-review.googlesource.com/c/go/+/366759
Trust: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>
Run-TryBot: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>
Reviewed-by: Bryan C. Mills <1c8aad60184261ccede67f5c63a0d2a3bf3c9ff4@google.com>
TryBot-Result: Go Bot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

golang/go,cloudflare/go,golang/go,cloudflare/go,CAFxX/go,golang/go,CAFxX/go,golang/go,CAFxX/go,nawawi/go,nawawi/go,CAFxX/go,nawawi/go,nawawi/go,CAFxX/go,cloudflare/go,golang/go,nawawi/go,cloudflare/go,nawawi/go,golang/go,nawawi/go,CAFxX/go,nawawi/go,CAFxX/go,golang/go,cloudflare/go,CAFxX/go,cloudflare/go,cloudflare/go,golang/go,cloudflare/go