Go: access: Gerrit Approver Access ("approvers")

See https://golang.org/wiki/GerritAccess

Request for +2 powers: https://go-review.googlesource.com/#/admin/groups/1005,members

gerrit name: Iskander Sharipov
gerrit email: iskander.[email protected]

CLs: https://go-review.googlesource.com/q/owner:iskander.sharipov%2540intel.com

Worked closely with:
cmd/internal/obj
cmd/internal/obj/x86
cmd/asm/internal/...
Touched several times:
cmd/compile/internal/gc
cmd/compile/internal/ssa
cmd/lint/internal/ld

Raionale: mostly for convenience on contributors workshops.
Organized myself: https://github.com/Quasilyte/kfu-go-2018
Planning to be available online for https://www.meetup.com/Go-London-User-Group/events/251046966/?_cookie-check=3YXhrv45XhjlkFMI
Hopefully, I'll be participating in other upcoming Go contributors workshop in https://www.gophercon.co.uk/ as a mentor ("live" this time).
There are also plans for other contributors workshop in Russia I'm going to organize this autumn.

Thank you.

CC @bradfitz @mvdan