math/bits: fix incorrect doc strings for TrailingZeros functions
math/bits: fix incorrect doc strings for TrailingZeros functions

Change-Id: I3e40018ab1903d3b9ada7ad7812ba71ea2a428e7
Reviewed-on: https://go-review.googlesource.com/37456
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

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