Variable thread count for multi-threaded GEMMs

Add trivial smoketest for xpotrf

m, n, and k can be set to arbitrary constants. A and B matrices can be transposed independently.

Rewrite NOFORTRAN conditionals

... so that they do not trigger accidentally when NOFORTRAN is empty/unset

Added mips I6500 core

Signed-off-by: Shivraj Patil <shivraj.patil@imgtec.com>

Add support for TARGET=ZARCH_GENERIC and TARGET=Z13

(Plain make) build system fixes for AIX

- retry fortran compiler test with aix-specific option if generic -m32/-m64 fails
- pass any custom ARFLAGS to lapack
- no addition of -m32/-m64 to the CFLAGS and FFLAGS on AIX

Fix cols/rows mixup in omatcopy 2nd step for BlasTrans cases

Equivalent of #1244 (issue #899) for the non-complex cases. Fixes #1289

Remove default FEXTRALIBS in NOFORTRAN case

Optimized standard Blas Level-1,2 (excluding nrm2 functions) for z13 (double precision). Issue 884

More canonical installation on Cygwin

Fix thread data races uncovered by gcc thread sanitizer

... as the "allocation" code jumped to now does UNLOCK_COMMAND instead of blas_unlock

* The DLL is named cygopenblas.dll, not libopenblas.dll
* The import lib (still called libopenblas.dll.a) is installed

Use in-place transform shortcut only if matrix is square

Fix coretype detection for Bay Trail Atom

My earlier PR #982 appears to have been incomplete in this regard - fixes #1285

fix detection of generic ARMv8 CPUs

Make: fix installation instructions

ARM: do not add linker flag `-lm` unconditionally

ARM: recognize gfortran pre-releases

The installation instructions as shown after successfully compiling
OpenBLAS are wrong because this arguments used during compilation have
to be provided to Make again.

On ARM the required math library depends on whether the soft floating
point ABI is used or not but this is already handled in
`Makefile.system`, lines 499-505.

Without proper recognition of gfortran versions such as
> GNU Fortran (GCC) 4.9.x 20150123 (prerelease)
OpenBLAS assumes the presence of the G77 compiler. Consequently,
`-lgfortran` is missing from the pkg-config file.

The aforementioned compiler is the gfortran compiler in the Android repo
in a commit tagged as `ndk-r14`, cf. Paul Mustière's gfortran build
instructions for Android at https://github.com/buffer51/android-gfortran

Support DYNAMIC_ARCH with CMake

Travis: Add jobs building with clang and disable job `LINUX64_MUSL USE_OPENMP=1`

,,,to see if this has any influence on the recent ld SIGKILLS

Make sure that range limit of last thread never exceeds data size

Support compiling with clang on windows

https://github.com/xianyi/OpenBLAS/pull/1255#issuecomment-320494610