Version: Add MAVLink git hash to available versions

src/lib/version/version.c

@@ -254,6 +254,11 @@ uint64_t px4_firmware_version_binary(void)
 	return PX4_GIT_VERSION_BINARY;
 }
 
+uint64_t px4_mavlink_lib_version_binary(void)
+{
+	return MAVLINK_LIB_GIT_VERSION_BINARY;
+}
+
 uint64_t px4_os_version_binary(void)
 {
 	//TODO: get NuttX version via git tag

src/lib/version/version.h

@@ -123,6 +123,11 @@ __EXPORT const char *px4_firmware_version_string(void);
  */
 __EXPORT uint64_t px4_firmware_version_binary(void);
 
+/**
+ * MAVLink lib version in binary form (first part of the git tag)
+ */
+__EXPORT uint64_t px4_mavlink_lib_version_binary(void);
+
 /**
  * Operating system version in binary form (first part of the git tag)
  * @return this is not available on all OSes and can return 0