parsebin: fix compilation problem with Visual C++ 2017
Right now I constantly get the following error during compilation, because VC2017 treats .c files as C++ by default
../subprojects/gst-plugins-base/gst/playback/gstparsebin.c(1793): error C4047: '==': 'const GstSegment *' differs in levels of indirection from 'int'
This patch fixes the problem.
WMBR, George Hazan