Convert fsbtoblk() from a macro to a function.  The redundant instances of 64-bit arithmetic were costing 775 bytes, and the inlining offered no benefit.  Moreover, ambiguity as to the argument types led to the introduction of a bug (see rev 1.56).
Convert fsbtoblk() from a macro to a function.  The redundant
instances of 64-bit arithmetic were costing 775 bytes, and the
inlining offered no benefit.  Moreover, ambiguity as to the argument
types led to the introduction of a bug (see rev 1.56).

Also, remove some casts that are now clearly redundant.

Inspired by:	67467

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase