[PyQt] Private sip modules not ending in .sip

[Scott Talbert]

Hi,

It seems that private sip modules cannot end in something other than sip 
(wxpython uses siplib).

[sip-4.19.18]$ mkdir build
[sip-4.19.18]$ cd build
[build]$ python3 ../configure.py --sip-module=wx.siplib
This is SIP 4.19.18 for Python 3.7.4 on linux.
The SIP code generator will be installed in /usr/bin.
The sip.h header file will be installed in /usr/include/python3.7m.
The wx.siplib module will be installed in
/usr/lib64/python3.7/site-packages/wx.
The sip.pyi stub file will be installed in
/usr/lib64/python3.7/site-packages/wx.
The default directory to install .sip files in is /usr/share/sip.
Creating sipconfig.py...
Creating top level Makefile...
Creating sip code generator Makefile...
Creating sip module Makefile...
[build]$ grep -rsI sip.so *
installed.txt:/usr/lib64/python3.7/site-packages/wx/sip.so
siplib/Makefile:TARGET = sip.so
[build]$

It seems that there are a couple places where sip is hard-coded, namely 
siplib/siplib.sbf and in create_makefiles in configure.py.

Scott