boards/modalai: separate voxl2 builds into two board builds instead of single board build with different variants

* Made voxl2 apps processor and slpi dsp processor builds into separate board builds so that they can
more easily be configured independently.

* Removed board specific link library command from px4_config.cmake and moved it to a more generic
board specific solution that can be used by any board that needs custom link libraries.

* Removed redundant cmake command for Qurt

* Removed unused definition from Qurt cmake file

* Removed unnecessary QURT_LIB cmake function

* Reorganized the voxl2 build structure to avoid 4 level board directories.

* Reverted cmake files to remove 4 level board naming code

* Updated documentation

boards/modalai/voxl2/scripts/build-apps.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+echo "*** Starting apps processor build ***"
+
+source /home/build-env.sh
+
+make modalai_voxl2
+
+cat build/modalai_voxl2_default/src/lib/version/build_git_version.h
+
+echo "*** End of apps processor build ***"

boards/modalai/voxl2/scripts/build-slpi.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+echo "*** Starting qurt slpi build ***"
+
+source /home/build-env.sh
+
+make modalai_voxl2-slpi
+
+cat build/modalai_voxl2-slpi_default/src/lib/version/build_git_version.h
+
+echo "*** End of qurt slpi build ***"

boards/modalai/voxl2/scripts/clean.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+# Clean out the build artifacts
+source /home/build-env.sh
+make clean

boards/modalai/voxl2/scripts/install-voxl.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+
+# Push slpi image to voxl2
+adb push build/modalai_voxl2-slpi_default/platforms/qurt/libpx4.so /usr/lib/rfsa/adsp
+
+# Push apps processor image to voxl2
+adb push build/modalai_voxl2_default/bin/px4 /usr/bin
+
+# Push scripts to voxl2
+adb push build/modalai_voxl2_default/bin/px4-alias.sh /usr/bin
+adb push boards/modalai/voxl2/target/voxl-px4 /usr/bin
+adb shell chmod a+x /usr/bin/px4-alias.sh
+adb shell chmod a+x /usr/bin/voxl-px4
+
+# Push configuration file
+adb shell mkdir -p /etc/modalai
+adb push boards/modalai/voxl2/target/voxl-px4.config /etc/modalai
+
+adb shell sync

boards/modalai/voxl2/scripts/run-docker.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+
+# Run this from the px4 project top level directory
+docker run -it --rm -v `pwd`:/usr/local/workspace rb5-flight-px4-build-docker