RCG: Add automated tests for building, installing and running models.

See merge request cds/advligorts!293

Some code cleanup, and fixing userspace builds after the last pull request.

See merge request cds/advligorts!304

Adding volatile for memory mapped IO, adding function for kernel space...

See merge request cds/advligorts!300

Fixing typo in file_operations data members

See merge request cds/advligorts!303

Removing the unneeded ExtraSymbols.symvers and cleaning up the FE makefile so...

See merge request cds/advligorts!302

Removing the unneeded ExtraSymbols.symvers and cleaning up the FE makefile so it builds on debian 11

Adding volatile for memory mapped IO, adding function for kernel space timespec retrieval and adding test for the gpstime module

Fixing permissions on scripts that I changed

See merge request cds/advligorts!299

Cleaning up findSharedMemory usage, fixing error checks on the returned...

See merge request cds/advligorts!297

Remove shared files causing collisions when generating the code for two models at the same time. Also speed up generation time by 10s per model.

See merge request cds/advligorts!296

Reduce foot print of cycle1 -> cycle2 dma size change for fast adcs.

See merge request cds/advligorts!298

Old code for changing DMA size from the ( possibly smaller ) first cycle
was too expensive in some sense, causing momentary channel hopping on the
ADC when run at 65k and time_shift=0.

The new code just changes the size value of an already existing DMA
module instead of totally recreating it.

Cleaning up findSharedMemory usage, fixing error checks on the returned pointer, consolidating code for findSharedMemory() and findSharedMemorySize() so we don't have duplicate, removing unused sprintf in both functions

The feCodeGen.pl script was using ./diags.txt and ./diags2.txt to build the <model>_partConnectionList.txt for each model. This meant that multiple models could not be built at the same time bacause they were sharing the diags files. This commit replaces those file with ones specific to the model being built. We also clean up the code a bit and remove some sleeps that slow down builing the models by 10 s each.

Shared memory cleanup 1

See merge request cds/advligorts!295

Modify test/x1tst.mdl to include every part that still works (MATRIX is broken).
Add tests to build, install and run models.
/opt/rtcds needs to work and be writeable by the testing user for install and run to work.
tests are part of cmake and run with ctest on the command line.

 * typeo in one of the commits left it as the invalid 'lingo_ioremap.h' instead of 'ioremap_selection.h'

Remove all references to ioremap_nocache and replace with the LIGO_IOREMAP macro.

See merge request cds/advligorts!292

 * ligo_iomap.h becomes iomap_selection.h to denote what it actually does.
 * LIGO_IOREMAP becomes simply IOREMAP to note that it isn't LIGO specific.