Add libtommath and libtomcrypt

[vitkabele]

Description

During my attempts to port the Firebird SQL database (related to #5795), I came across the need of also porting the dependent libtommath and libtomcrypt libraries.
Not knowing how my attempts with Firebird will end, I'd like to share the intermediate results with the community. My changes do not create new package, just provides libraries that can be used during the build of dependent software.

Both libraries compile with make all-supported and place the library objects in the destination directory.

I will be glad for any feedback.

Thank you.

Checklist

• Build rule all-supported completed successfully (yes for both)
• New installation of package completed successfully (no package, just library in cross/)
• Package upgrade completed successfully (Manually install the package again)
• Package functionality was tested
• Any needed documentation is updated/created

Type of change

• Bug fix
• New Package
• Package update
• Includes small framework changes
• This change requires a documentation update (e.g. Wiki)

[vitkabele]

I found out that these won't be needed for the Firebird package in the end. I would need them in native/ instead of cross. I did not fully understand the Firebird compilation process initially.
They can however still be merged if you think someone would benefit from them.

[vitkabele]

So, the libtom* libraries are not needed for cross/, but in native/. I have both versions and I can push all of them. The native/libtom* are however part of my Firebird branch and I can merge them eventually all together with the Firebird

[vitkabele]

After further investigation, these won't be needed at all for FirebirdSQL spk. Closing this pull request as it is no longer relevant.