Clean up spurious unused variables in the kernels

l2 cache size is not universally needed to assign default unrolling limits, but neither putting its declaration inside an ifdef nor cloning it into all ifdef sections that need it really makes sense here.

(Trivial) optimized dsdot implementation for HASWELL

While debugging/profiling applications using perf or other tools, the
kernels appear scattered in the profile reports. This is because the labels
within the kernels are not local and each label is shown as a separate
function.

To avoid this, all the labels within the kernels are changed to local
labels.

* prebuild.cmake: Put quotes around path names that may contain whitespace
(Copied from alexkaratakis' PR #1295)
* kernel/CMakeLists.txt: Fix common_lapack header inclusion and DYNAMIC_ARCH generation of ?neg_tcopy and ?laswp_ncopy files
* lapack/CMakeLists.txt: Use correct template for ?laswp_(plus,minus) functions

Fix out-of-bounds memory accesses exposed by xccblat3 testcase

Save and restore VSX registers

...and does not appear to be needed even when it stays within the bounds of the array

CMake improvements

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

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

Fix typos and bad if statements discovered in 0.2.20.

TODO: Fix the parser macro to strip trailing whitespaces

arm: Fix clang compilation for ARMv7

clang is not recognizing some pre-UAL VFP mnemonics like fnmacs, fnmacd,
fnmuls and fnmuld. Replaced them with equivalent UAL mnemonics which are
vmls.f32, vmls.f64, vnmul.f32 and vnmul.f64 respectively.

Optimise loads on Power9 LE

Since softfp code has been added to all required vfp kernels,
the code for auto detection of abi is no longer required.

The option to force softfp ABI on make command line by giving
ARM_SOFTFP_ABI=1 is retained. But there is no need to give this option
anymore.

Also the newly added C versions of 4x4/4x2 gemm/trmm kernels are removed.
These are longer required. Moreover these kernels has bugs.