* Move accesses to the overflow flag into the scope of the blas lock

*  return OMP places (if available, or SC_NPROCESSORS_CONF) for maximum thread count when built with OpenMP

Add pointers to the definition of the hardware capability flags in glibc
and describe how they relate to the levels CPU_Z13 and CPU_Z14 for
optimized kernels.

To aid identifying available hardware capabilities and in debugging
potential build issues, dump their value in dynamic_arch_init() when
OPENBLAS_VERBOSE is set to 2 or higher.

Signed-off-by: Marius Hillenbrand <mhillen@linux.ibm.com>

On s390x, the run-time detection for DYNAMIC_ARCH and the compile-time
choice in cpuid_zarch use different methods for identifying the
supported CPU features. To make cpuid_zarch future-proof and both easier
to maintain, switch cpuid_zarch to the same mechanism as DYNAMIC_ZARCH
(i.e., derive the supported CPU features from hwcap flags) and share
code between both (in a new header cpuid_zarch.h).

Signed-off-by: Marius Hillenbrand <mhillen@linux.ibm.com>

Signed-off-by: JonasZhou <JonasZhou@zhaoxin.com>

blas_server_avail was read without holding server_lock. If multiple threads call blas_thread_shutdown simultaneously, for example, by calling fork(), then they can attempt to shut down multiple times. This can lead to a segmentation fault.

Fix get_num_procs()  in the USE_TLS branch for non-glibc systems

add embedded option

Fix null pointer check in blas_memory_alloc

fixes #3074