[OpenBLAS]: benchmark error of potrf

[description]: when the matrix size goes higher than 5800 during the cpotrf test, error info, such as "Potrf info = 5679", will be returned on ARM64 and x86 machines. Uplo = L & F.
[solution]: changed the func for building the matrix so that the complex Hermitian matrix can stay positive definite during the computation.
[dts]:

Update and reformat README

Add a drone.io multithread test for x86_64

This patch adds support for bfloat16 data type matrix multiplication kernel.
For architectures that don't support bfloat16, it is defined as unsigned short
(2 bytes).  Default unroll sizes can be changed as per architecture as done for
SGEMM and for now 8 and 4 are used for M and N.  Size of ncopy/tcopy can be
changed as per architecture requirement and for now, size 2 is used.

Added shgemm in kernel/power/KERNEL.POWER9 and tested in powerpc64le and
powerpc64.  For reference, added a small test compare_sgemm_shgemm.c to compare
sgemm and shgemm output.

This patch does not cover OpenBLAS test, benchmark and lapack tests for shgemm.
Complex type implementation can be discussed and added once this is approved.

Add a read memory barrier to the traversal of the buffer slot list

Handle unaligned data in the SSE2 copy kernel

should have no performance impact on reasonably modern cpus and fixes occasional crashes in actual user code.

Needed on systems with weak memory ordering - the inferior, partially working fix from #2544 was already removed in #2551

rebase

Increase BUFFER_SIZEs and add a safeguard; supply GEMM_R for POWER8/9

As shown in #2538, default buffersizes on some platforms were smaller than required in memory.c
and the requirement could never be fulfilled for a calculated GEMM_R on PPC given the fomula used

rebase

Add API to set thread affinity on Linux.

libname: treat FreeBSD and DragonFly like linux and sunos

Add a GENERIC target for 64bit MIPS

Match thread count in cpp_thread_test to host capability

Using "make TARGET=GENERIC" on loongson platform will get the following
error messages:
"make[1]: *** No rule to make target 'sgemm_incopy.o', needed by 'libs'"
Add kernel/mips64/KERNEL.generic to slove the problem.

Issue: #2545

* Add another memory barrier in memory.c to prevent races in memory slot allocation

* Add an all-core test on Drone.io's ThunderX platform and modify dgemm_tester to use all 96 cores

Add a Z13 build to the Travis configuration (#2542)

Revert 42 z12ci to keep forked develop clean