re-enable C_LAPACK for MSVC in CMAKE

Adapt commands for tests with GNU make.

* Add C equivalents of the Fortran routines from Reference-LAPACK as fallbacks, and C_LAPACK variable to trigger their use

Consolidate actions on GitHub runners.

Fix missing braces from previous commit (PR3600)

Re-organize build matrix for Ubuntu and MacOS runners.
Don't start runners that don't do anything.
Run tests.

* limit flang optimizations to -O2

Fix build targets in Makefile.prebuild

* Prevent addition of a BOM to test input (which would distort the names of output files)

- config.h was used as target even when it wasn't generated.
  This only worked because the 'dummy' target always triggers
  a full rebuild.
  It is however better to specify the exact target that is to
  be rebuilt do avoid confusion.
- Explicitly mark 'dummy' as a 'phony' target.

Signed-off-by: Egbert Eich <eich@suse.com>

Add action for MSYS2 builds.

Fix LAPACKE with 64-bit indexing on Windows.

Fix mistaken declaration of CortexX1 as ArmV9 in PR#3586

Do not include symbols defined in driver/others/parameter.c in DYNAMI…

driver/others/parameter.c does not get build during DYNAMIC_ARCH, thus,
do not declare its symbols. This will make the build fail early and in
an obvious way if functions are trying to use these symbols.

Signed-off-by: Egbert Eich <eich@suse.com>

Use CC and full command line instead of hard-coding gcc for AVX512 ch…

Hard-coding gcc may not provide incorrect results when a different compiler
for the target build is used. To remain in sync with the main call to c_check,
pass the full command line.

Signed-off-by: Egbert Eich <eich@suse.com>

Initial support for M1 on Linux, Phytium FT2000 series, ARMV9 Cortex X1,X2,A510,A710

Revert accidental change of generic ARMV8 DGEMM parameters from #3425

Add a (CMAKE) option to skip the LAPACK testsuite and use it in Azure CI

Port changes from upstream Reference-LAPACK.