japanese/kdrill: fix build

This adds a missing parenthesis to $(LOCALBASE).
It is unclear why this hasn't been noticed earlier.

While we are at it, define LICENSE.

Fixes: 2546bd0290761071e3ad392427d7c2ba4e5a396b
Approved by: portmgr (build fix blanket)
MFH: 2026Q1
Sponsored by: Raptor Computing Systems, LLC

(cherry picked from commit 8552be0c42f43fbc0a2db02c7982e8355c6b52a4)