FIPS module checksums: add scripts and Makefile rule

FIPS module checksums: add scripts and Makefile rule

This adds the following scripts:

util/lang-compress.pl:

Compress source code, which language is determined by the first argument.
For the moment, we know 'perl' (perlasm source code), 'C' (C source code)
and 'S' (Assembler with C preprocessor directives).
This removes comments and empty lines, and compresses series of horizontal
spaces to one single space in the languages where that's appropriate.

util/fips-checksums.sh:

Takes source file names as arguments, pushes them through
util/lang-compress.pl and unifdef with FIPS_MODE defined, and calculates
the checksum on the result.

Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/8871)