testhal stm32lxx/dac and minor improvements in the dac-new

Hi Mobyfab,

You have seen me at IRC ChibiOS channel as beaming.

I attempted to pord dac-new to stm32lxx. Which is mostly copy-pasting from other stm32 architectures.
testhal/dac compiles just fine, but hardware DAC does not respond properly, I suspect wrong DMA setting.

If you can, please, have a look and let me know what I need to improve/redo. Note that some of the patches are stm32lxx agnostic: "added missing tim related include". This is missing so even your testhal F0 does not compiles with out applying it.

Any feedback will be appreciated.