firmware: Handle new mag_cal.c location and dependencies

The mag_cal.c file was moved and the files were updated, but
the makefile fragments used for the GNU Make system were not updated.

Additionally, the mag_cal.c file now depends on the kasa.c math
functions and diversity_checker.c, so these files must also be

Bug: 112656064
Test: local build test only
Change-Id: Ida6515ae2c37479889cb916399b1cf5a7d6ee8c5
8 files changed