add PRODUCT to version.h; handle empty PATCHVER (cherry picked from commit b0f3042e37c697759903b15442bacbce0f873fc9)
add PRODUCT to version.h; handle empty PATCHVER
(cherry picked from commit b0f3042e37c697759903b15442bacbce0f873fc9)

each/bind9-collab,pecharmin/bind9,pecharmin/bind9,pecharmin/bind9,each/bind9-collab,pecharmin/bind9,pecharmin/bind9,each/bind9-collab,pecharmin/bind9,each/bind9-collab,each/bind9-collab,each/bind9-collab