Optimize RPCC function on ARM64

as I find conflicting information on accessibility from non-priviledged processes

* 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

Signed-off-by: Paul Osmialowski <pawel.osmialowski@arm.com>

Change the GEMM_P, GEMM_Q, GEMM_R values for Cortex A57

Co-Authored-By: Ralph Campbell <ralph.campbell@broadcom.com>

to be used on armv5 and new platforms

- use on arm, arm64 and any new platform
- use faster integer math instead of double
- use similar scale as rdtsc so that timeouts work

Optimizations for APM's xgene-1 (aarch64).

1) general system updates to support armv8 better.  Make all did not work, one needed to supply TARGET=ARMV8.
2) sgem 4x4 kernel in assembler using SIMD, and configuration changes to use it.
3) strmm 4x4 kernel in C.  Since the sgem kernel does 4x4, the trmm kernel must also do 4xN.

Added Dave Nuechterlein to the contributors list.

Signed-off-by: Timothy Gu <timothygu99@gmail.com>