cmd/compile: simplify and clean up inlnode
cmd/compile: simplify and clean up inlnode

Change-Id: I0d14d68b57e8605cdae8a45d6fa97255a42297d8
Reviewed-on: https://go-review.googlesource.com/37521
Run-TryBot: Josh Bleecher Snyder <cdc248cc4d32e4fbfe04e45228163bcecd48a0b9@gmail.com>
Reviewed-by: Matthew Dempsky <e56ac2c500064424afac424d4b5e53bd0570a731@google.com>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

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