* Use CMAKE_C_COMPILER_VERSION throughout

* Fix syntax in parsing of IFNEQ

`-exhaustive-register-search` is an LLVM code generation flag that shouldn't be passed directly to clang compiler.

* Filter out FFLAGS that flang-new from LLVM18 no longer supports

cmake/openblas.pc.in: fixed version and URL

Fix: build failed on LoongArch

According to the documentation at https://github.com/loongson/la-abi-specs/blob/release/lapcs.adoc#the-base-abi-variants, valid -mabi parameters are lp64s, lp64f, lp64d, ilp32s, ilp32f and ilp32d.

Fixes: https://github.com/OpenMathLib/OpenBLAS/issues/4376

Here a bit tricky things.

A value `CMAKE_SYSTEM_PROCESSOR` is came from output of `uname -m` which
migth be 32bit with 64bit building applicaiton.

So, for that case use `CMAKE_SIZEOF_VOID_P` to detect the target.

See https://trac.macports.org/ticket/68488

* Move ?GELQS and ?GEQRS from TESTING/LIN to DEPRECATED (Reference-LAPACK PR 900)

* Add f2c-converted versions of ?GELQS and ?GEQRS

Use defined variable for riscv64 in arch.cmake

Fix 64-bit fortran options for riscv64

64-bit builds are currently broken without this flag.

Makefiles have done this already: 5720fa02c5/Makefile.system (L831)

It's defined in #4137

In order to enable support for future cores which have similar tunings
(in this case I'm doing this for the Arm(R) Neoverse(TM) V2 core), this generically detects SVE support and enables it. This should better manage the size and complexity of dynamic dispatch rather than just copy pasting the same parameters.

To make `ARMV8SVE` more representive of the common 128-bit SVE case,
I've split it and similar parameters from A64FX which has the wider
512-bit SVE.

Fix armv8 detection in system_check.cmake

Fix riscv64 detection in system_check.cmake

The cmake scripts incorrectly treated armv8 as 32-bit arm, causing
compilation issues. This just adds 'armv8' to the arm64 condition check.