clang pretends to be gcc 4.2.0 which means we will
use inline asm for no reason, instead of builtins
on clang when possible.
Signed-off-by: Khem Raj <raj.khem@gmail.com>

- Optimizations set change. Now IPP integrations will provide code for SSE42, AVX2 and AVX512 (SKX) CPUs only. For HW below SSE42 IPP code is disabled.
- Performance regressions fixes for IPP code paths;
- cv::boxFilter integration improvement;
- cv::filter2D integration improvement;

- '-fvisibility' flag was updated
- PVAPI library detection was changed

It is configurable via OPENCV_CPUFEATURES_TARGET_NAME variable

https://sourceforge.net/p/predef/wiki/OperatingSystems

- ffmpeg 3.3 -> 3.3.2
- added VERSIONINFO

Remove unnecessary Non-ASCII characters from source code (#9075)

* Remove unnecessary Non-ASCII characters from source code

Remove unnecessary Non-ASCII characters and replace them with ASCII
characters

* Remove dashes in the @param statement

Remove dashes and place single space in the @param statement to keep
coding style

* misc: more fixes for non-ASCII symbols

* misc: fix non-ASCII symbol in CMake file

https://github.com/01org/IntelSEAPI/tree/master/ittnotify

without tests, testdata, .proto files

It used for Matlab binding only

Updated integrations for:
cv::split
cv::merge
cv::insertChannel
cv::extractChannel
cv::Mat::convertTo - now with scaled conversions support
cv::LUT - disabled due to performance issues
Mat::copyTo
Mat::setTo
cv::flip
cv::copyMakeBorder - currently disabled
cv::polarToCart
cv::pow - ipp pow function was removed due to performance issues
cv::hal::magnitude32f/64f - disabled for <= SSE42, poor performance
cv::countNonZero
cv::minMaxIdx
cv::norm
cv::canny - new integration. Disabled for threaded;
cv::cornerHarris
cv::boxFilter
cv::bilateralFilter
cv::integral

ffmpeg 3.2.1 -> 3.3
libvpx 1.6.0 -> 1.6.1

Tuned restrictions for Canny, Warp, FAST, Accumulate and Convolution OpenVX HAL calls on small images