sysmobts-calib: Warn about firmware and header mismatch
sysmobts-calib: Warn about firmware and header mismatch

sysmobts-calib might be easily patched by a user that does not know
that firmware and firmware headers form a contract that should be
matched. Compare the version numbers and print a warning if it does
not look correct. This should be enough for a user to see that something
is not right. Continue anyway as the firmware might still be compatible
(because the ABI has not changed).

Fixes: SYS#1172

osmocom/osmo-bts,osmocom/osmo-bts,osmocom/osmo-bts