Don't depend on the command for extra compilers automatically

For vcproj files we should not automatically add a dependency for extra
compilers as this should be done via the depends variable for the extra
compiler instead.

This fixes a problem where something like '@echo command' was used in the
command as it would depend on echo and not the actual command anyway.

Change-Id: I7c0aa0d62143aa39c518e8bce65f302afdba33c9
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>

qmake/generators/win32/msvc_objectmodel.cpp

@@ -2335,7 +2335,6 @@ bool VCFilter::addExtraCompiler(const VCFilterFile &info)
         CustomBuildTool.Outputs += out;
 
         deps += CustomBuildTool.AdditionalDependencies;
-        deps += cmd.left(cmd.indexOf(' '));
         // Make sure that all deps are only once
         QHash<QString, bool> uniqDeps;
         for (int c = 0; c < deps.count(); ++c) {