cmd/compile: use keyed struct for asm tests
cmd/compile: use keyed struct for asm tests

Just to make it clearer which regexps are positive and which
regexps are negative.

Change-Id: Ia190e89be28048fcae2491506f552afad90a5f85
Reviewed-on: https://go-review.googlesource.com/59490
Run-TryBot: Keith Randall <8c99c3a9284e493be632950b84cd789d08ed3e9d@golang.org>
Reviewed-by: Martin Möhrmann <9c82b83f348009b39856043bb9ed3ef41e171aeb@google.com>
Reviewed-by: Ilya Tocar <112830fdd81fb6e3c10661fec6ab883a8a8a909f@intel.com>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

polyverse-security/go,codestation/go,golang/go,polyverse-security/go,CAFxX/go,Cofyc/go,Cofyc/go,nawawi/go,codestation/go,nawawi/go,golang/go,josharian/go,CAFxX/go,cloudflare/go,cloudflare/go,Cofyc/go,akutz/go,akutz/go,nawawi/go,golang/go,golang/go,golang/go,christopher-henderson/Go,Cofyc/go,akutz/go,cloudflare/go,CAFxX/go,Cofyc/go,josharian/go,polyverse-security/go,akutz/go,josharian/go,josharian/go,akutz/go,akutz/go,polyverse-security/go,josharian/go,polyverse-security/go,CAFxX/go,josharian/go,codestation/go,codestation/go,codestation/go,Cofyc/go,cloudflare/go,polyverse-security/go,josharian/go,CAFxX/go,golang/go,cloudflare/go,nawawi/go,codestation/go,Cofyc/go,golang/go,CAFxX/go,nawawi/go,josharian/go,nawawi/go,nawawi/go,golang/go,codestation/go,CAFxX/go,akutz/go,Cofyc/go,cloudflare/go,nawawi/go,cloudflare/go,codestation/go,cloudflare/go,CAFxX/go,polyverse-security/go,polyverse-security/go,akutz/go