Support QEMU virtual cpu in 64bit mode as CORE2 or BARCELONA

Some QEMU instances pretend to be "AuthenticAMD" with the same family 6/model 6 even when running on an Intel host
(could be related to qemu or libvirt version and/or kvm availability). Also fix the define to depend on __x86_64__ set by the
compiler, the defines using __64BIT__ will only work for getarch_2nd.

qemu itself claims it is a 64bit P6, which does not exist in the wild.

* Add automatic fixups for OSX/IOS cross-compilation

* Add OSX/IOS cross-compilation test to Travis CI

* Handle platforms that lack hwcap.h by falling back to ARMV8

* Fix PROLOGUE for OSX/IOS

Add overlooked part of IOS compilation fix

sync with upstream

Rewrite ARMV8 code to allow cross-compilation for IOS

Revert "Avoid taking root of negative number in symv_thread.c"

... which does not perform the automatic numbering on instantiation that the _@ suffix signifies

os version 10.13 "High Sierra" appears to be the oldest release now for which Homebrew provides a gcc package.
Anything older and the Travis job will run out of time building gcc from source

in response to Homebrew updates

Avoid taking root of negative number in symv_thread.c

This is similar to fixes in gh-1929, but there was one remaining
occurance of this type of pattern in the driver/level2/*_thread.c
files.

fixed bug power9 strmm . BLAS-TESTER passes

Ppc fixes

update

There is currently no simple way to query cache sizes on ARMV8, so this takes the number of cores as a trivial indication if the target is a server-class device with a big cache, or just a single-board toy or smartphone.

* Add gcc7-generated assembly files for POWER8/9 isa/ica-min/max and POWER9 caxpy

To work around internal compiler errors encountered when compiling the original C source with gcc 4 and 5, and wrong code generated by gcc 8.3.0

* Use gcc-generated assembly instead of original C sources

to work around internal compiler errors encountered with gcc 4.8/5.4 and wrong code generation by gcc 8.3

* Use gcc-generated assembly instead of the original C source

to work around internal compiler errors encountered with gcc 4.8 and 5.4, and wrong code generation by gcc 8.3

* Add gcc7-generated assembler version of caxpy for power8

to work around wrong code generated by gcc 8.3

* Handle CONJ define for caxpyc

* Handle CONJ define for caxpyc

* Add gcc7-generated assembly cdot for POWER9

* Use prebuilt assembly for POWER9 cdot

created with gcc 7.3.1 to work around ICE in older gcc versions

* Exclude POWER9 from DYNAMIC_ARCH when gcc versions is lower than 6

* Update Makefile.system

* Use PROLOGUE macro to ensure correct function name for DYNAMIC_ARCH

* Disable POWER9 with old gcc versions

* Revert #2051 and add a better fix for TARGET=generic with DYNAMIC_ARCH
fixes #2257 without breaking #2048 again

update to current develop

Optimized ?trtrs

Address minor warnings popping up in gcc7+

* Fix compiler identification and option setting

* Handle BINARY=32 option on X86_64

* Add xGEMM3M unroll parameters for crossbuild-target CORE2

* Replace bogus mingw64/32bit CI job with actual 32bit build

mingw64 is not multilib-capable, so using an x86_64-mingw with BINARY=32 in the CI was not going to work anyway (but build passed while BINARY=32 was ignored).