zlib patch to use std name for lib.

Use a standard name libz.(so|a) if we are using mingw (as we do on linux).

This patch somehow deprecate the previous commit (patch) but both patches
are the right thing to do.
We need this one especially for others dependencies using pkg-config.
The generated .pc always use the '-lz' option and so, we need the correct
names for the lib.

kiwix-build.py

@@ -752,6 +752,7 @@ class zlib(Dependency):
     class Source(ReleaseDownload):
         archive = Remotefile('zlib-1.2.8.tar.gz',
                              '36658cb768a54c1d4dec43c3116c27ed893e88b02ecfcb44f2166f9c0b7f2a0d')
+        patches = ['zlib_std_libname.patch']
 
     class Builder(CMakeBuilder):
         @property