Fix missing -mfma compiler flag in cmake builds without DYNAMIC_ARCH

rebase

Merge branch 'openblas-open-910' of git://github.com/damonyu1989/OpenBLAS into damonyu1989-openblas-open-910

Improve the performance of rot by using AVX512 and AVX2 intrinsic

Fix missing AVX2 and FMA3 capabilities in FORCE_target mode

Optimize sdot/ddot for POWER10

Fix handling of cpu capability flags in DYNAMIC_ARCH builds

This patch makes use of new POWER10 vector pair instructions for
loads and stores.

rebase

Fix macro name used in ifdef for POWERPC/PGI

Ensure that EXPRECISION is disabled for DYNAMIC_ARCH with TARGET=GENERIC and fix CMAKE DYNAMIC_ARCH builds

POWER10:  Change dgemm unroll factors

Allows to create a library with a different
SONAME without the need to add suffixes to symbols
Backwards compatible and should have no effect
on the workflow and previous users.
Useful for allowing INTERFACE64 library alongside
the standard library without file conflicts

NO_EXPRECISION is disabled for the GENERIC_TARGET already, so prevent mixing with code parts that use a different float size by default

add openbsd 68+ gfortran name

Reunify default BUFFER_SIZE on ARM64 to avoid crashes in DYNAMIC_ARCH mode

Changing the unroll factors for dgemm to 8 shows improved performance with
POWER10 MMA feature.   Also made some minor changes in sgemm for edge cases.

rebase

fix avx2 detection