Otherwise this fails to build ( found on mips )

Fixes
contrib/modules/surface_matching/src/hash_murmur86.hpp:97:15: error:
expected constructor, destructor, or type conversion before '(' token
     && defined(__GNUC__) && (__GNUC__>4 || (__GNUC__==4 &&
__GNUC_MINOR__>=3))
               ^

according new behavior of SubDiv2D

* Correction for computeBinaryMap crash:
- the function staticSaliencyFineGrained::computeSaliency() outputs a
normalized floating point image
- Add an assert in StaticSaliency::computeBinaryMap in order to check
image depth (must be CV_32F)

* - Change assert in cv::Saliency::StaticSaliency::computeBinaryMap()
- Change normalization factor in cv::Saliency::StaticSaliencyFineGrained::computeSaliencyImpl()