cmd/compile/internal/syntax: remove strbyteseql
cmd/compile/internal/syntax: remove strbyteseql

cmd/compile already optimizes "string(b) == s" to avoid allocating a
temporary string.

Change-Id: I4244fbeae8d350261494135c357f9a6e2ab7ace3
Reviewed-on: https://go-review.googlesource.com/28931
Run-TryBot: Matthew Dempsky <e56ac2c500064424afac424d4b5e53bd0570a731@google.com>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

Cofyc/go,josharian/go,vsekhar/elastic-go,goodlang/good,derekmarcotte/go,codestation/go,josharian/go,suncycheng/go,polyverse-security/go,ImJasonH/go,akutz/go,momchil-velikov/go,cloudflare/go,vsekhar/elastic-go,suncycheng/go,ImJasonH/go,linux-on-ibm-z/go,linux-on-ibm-z/go,Cofyc/go,akutz/go,golang/go,ImJasonH/go,polyverse-security/go,akutz/go,ImJasonH/go,CAFxX/go,goodlang/good,Cofyc/go,cloudflare/go,vsekhar/elastic-go,codestation/go,suncycheng/go,nawawi/go,vsekhar/elastic-go,polyverse-security/go,ImJasonH/go,josharian/go,nawawi/go,derekmarcotte/go,christopher-henderson/Go,golang/go,polyverse-security/go,linux-on-ibm-z/go,nawawi/go,vsekhar/elastic-go,cloudflare/go,polyverse-security/go,CAFxX/go,goodlang/good,nawawi/go,polyverse-security/go,cloudflare/go,CAFxX/go,golang/go,nawawi/go,golang/go,goodlang/good,polyverse-security/go,vsekhar/elastic-go,CAFxX/go,suncycheng/go,cloudflare/go,nawawi/go,akutz/go,momchil-velikov/go,ImJasonH/go,derekmarcotte/go,vsekhar/elastic-go,linux-on-ibm-z/go,nawawi/go,Cofyc/go,momchil-velikov/go,codestation/go,momchil-velikov/go,cloudflare/go,golang/go,codestation/go,suncycheng/go,josharian/go,suncycheng/go,akutz/go,nawawi/go,momchil-velikov/go,codestation/go,goodlang/good,CAFxX/go,CAFxX/go,josharian/go,linux-on-ibm-z/go,derekmarcotte/go,CAFxX/go,cloudflare/go,akutz/go,goodlang/good,derekmarcotte/go,goodlang/good,josharian/go,josharian/go,derekmarcotte/go,ImJasonH/go,ImJasonH/go,vsekhar/elastic-go,josharian/go,CAFxX/go,codestation/go,derekmarcotte/go,linux-on-ibm-z/go,codestation/go,momchil-velikov/go,momchil-velikov/go,golang/go,akutz/go,linux-on-ibm-z/go,codestation/go,polyverse-security/go,linux-on-ibm-z/go,momchil-velikov/go,Cofyc/go,golang/go,cloudflare/go,Cofyc/go,suncycheng/go,akutz/go,Cofyc/go,Cofyc/go,goodlang/good,derekmarcotte/go,golang/go,suncycheng/go