tdf#114025 - minimal and not entirely convincing fix for assertion failure.

Almost certainly most of the sfx code needs guarding with the SolarMutex.

Change-Id: Ied52f1e57c44c20486777e08a901060c191043a2
Reviewed-on: https://gerrit.libreoffice.org/45233Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Michael Meeks <michael.meeks@collabora.com>

sfx2/source/appl/appinit.cxx

@@ -218,6 +218,7 @@ void SfxApplication::Initialize_Impl()
 
     if (!utl::ConfigManager::IsFuzzing())
     {
+        SolarMutexGuard aGuard;
         //ensure instantiation of listener that manages the internal recently-used
         //list
         SfxPickList::ensure();