games/barony: Fix build on armv7
The type real_t is float on ARM but double on other platforms. Pepper
in a bunch of extra casts to make clang happy.
The alternative of making real_t a double on ARM does not work.
PR: 267442
Approved by: maintainer timeout, >2 weeks
MFH: 2022Q4
(cherry picked from commit 835b479670531fb700f0f3aad9333f121e144852)