regen/regcharclass.pl: Use smaller inRANGE version

regen/regcharclass.pl: Use smaller inRANGE version

The previous commit split inRANGE up so that code that was known to have
valid inputs to it could use a component that didn't have all the
compile-time checks (often duplicates) that otherwise are made.

This commit changes to use that component.  The reason the compile-time
checks are unnecessary here, is this is machine-generated code known to
meet the inRANGE input requirements.

All those compile-time checks added up to being too large for some
compilers to handle.