fix issue, then it wasn't possible to view FBD programs

the reason for that is possible wx-3.0-gtk2 bug that happens if
ALWAYS_SHOW_SB is set.

Traceback (most recent call last):
File "Beremiz.py", line 1045, in OnProjectTreeItemActivated
IDEFrame.OnProjectTreeItemActivated(self, event)
File "IDEFrame.py", line 1667, in OnProjectTreeItemActivated
self.EditProjectElement(item_infos["type"], item_infos["tagname"])
File "IDEFrame.py", line 1752, in EditProjectElement
new_window = Viewer(self.TabsOpened, tagname, self, self.Controler)
File "editors/Viewer.py", line 611, in __init__
EditorPanel.__init__(self, parent, tagname, window, controler, debug)
File "editors/EditorPanel.py", line 68, in __init__
self._init_ctrls(parent)
File "editors/EditorPanel.py", line 52, in _init_ctrls
self._init_Editor(self)
File "editors/Viewer.py", line 603, in _init_Editor
style=wx.HSCROLL | wx.VSCROLL | wx.ALWAYS_SHOW_SB)
File "/usr/lib/python2.7/dist-packages/wx-3.0-gtk2/wx/_windows.py", line 296, in __init__
_windows_.ScrolledWindow_swiginit(self,_windows_.new_ScrolledWindow(*args, **kwargs))
PyAssertionError: C++ assertion "scrolled" failed at ../src/gtk/scrolwin.cpp(205) in DoShowScrollbars(): window must be created

from ..toolchain_gcc import toolchain_gcc

class Xenomai_target(toolchain_gcc):
    dlopen_prefix = "./"
    extension = ".so"
    def getXenoConfig(self, flagsname):
        """ Get xeno-config from target parameters """
        xeno_config=self.CTRInstance.GetTarget().getcontent().getXenoConfig()
        if xeno_config:
            from util.ProcessLogger import ProcessLogger
            status, result, err_result = ProcessLogger(self.CTRInstance.logger,
                                                       xeno_config + " --skin=native --"+flagsname,
                                                       no_stdout=True).spin()
            if status:
                self.CTRInstance.logger.write_error(_("Unable to get Xenomai's %s \n")%flagsname)
            return [result.strip()]
        return []
    
    def getBuilderLDFLAGS(self):
        xeno_ldflags = self.getXenoConfig("ldflags")
        return toolchain_gcc.getBuilderLDFLAGS(self) + xeno_ldflags + ["-shared"]

    def getBuilderCFLAGS(self):
        xeno_cflags = self.getXenoConfig("cflags")
        return toolchain_gcc.getBuilderCFLAGS(self) + xeno_cflags + ["-fPIC"]