Fix arducam Simulator to Follow NOS3 Convention for bus tag nesting

[msuder]

Fix XML and hardware model XML parsing.

Wrong:

        <simulator>
            <name>camsim</name>
            <active>true</active>
            <library>libcam_sim.so</library>
            <hardware-model>
                <type>ARDUCAM_OV5640</type>
                <connections>
                    <connection><type>command</type><bus-name>command</bus-name><node-name>cam-command-node</node-name></connection>
                </connections>
                <!-- <stream_data>true</stream_data> -->
                <i2c>
                    <address>60</address>
                    <bus>i2c_2</bus>
                </i2c>
                <spi>
                    <bus>spi_0</bus>
                    <chip_select>0</chip_select>
                </spi>
            </hardware-model>

Right:

        <simulator>
            <name>camsim</name>
            <active>true</active>
            <library>libcam_sim.so</library>
            <hardware-model>
                <type>ARDUCAM_OV5640</type>
                <connections>
                    <connection><type>command</type><bus-name>command</bus-name><node-name>cam-command-node</node-name></connection>
                    <connection><type>spi</type>
                        <bus-name>spi_0</bus-name>
                        <chip-select>0</chip-select>
                    </connection>
                    <connection><type>i2c</type>
                        <bus-name>i2c_2</bus-name>
                        <address>60</address>
                    </connection>
                </connections>
                <!-- <stream_data>true</stream_data> -->
            </hardware-model>

[msuder]

Other sims that need fixed (move bus info under <connections><connection>...): generic_css_sim.

[jlucas9]

This should be resolved as part of the #164 issue