devapp/owners: add martisch to internal/cpu, runtime and cmd/compile contacts
devapp/owners: add martisch to internal/cpu, runtime and cmd/compile contacts

runtime: mostly for maps, slices, utf8, string functions and cpu features.

Change-Id: I66765b1bdb4fb4dae1b28fb7a90c0ee23ce63112
Reviewed-on: https://go-review.googlesource.com/126595
Run-TryBot: Martin Möhrmann <9c82b83f348009b39856043bb9ed3ef41e171aeb@google.com>
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

golang/build,golang/build,golang/build,golang/build