Commit eba7fb5f9f modified the definition
of struct dns_rbtnode. Doing that changes the layout of map-format zone
files. Bump MAPAPI and update the offsets used in map-format zone file
checks in the "masterformat" system test, as these changes were
inadvertently omitted from the aforementioned change.
(cherry picked from commit 52fe0b6be7)
b138931fc0